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Half a V6.......
clairetoo - 17/11/13 at 02:13 PM

I've got the current Mx5 V6 to the point where it should run - but have spent the last week going around in circles . It will run , but only on three cylinders..........
Its an identical set-up to mine , and so far I have swapped the ECU , EDIS , and coil / leads over to my car (one at a time) and every time mine starts and runs fine . So many hours have been spent checking and double checking the wiring , and no problems found .
Its one whole bank that wont run - I even had the injectors and fuel rail hanging out still connected this morning , and all appears to work as intended .
I've checked the cam timing , and ignition timing , and got the throttle bodies as near to balanced as possible - and still only the one side running......................

Any ideas ?


MikeRJ - 17/11/13 at 02:28 PM

That's a real puzzler. Have you tried a compression test just to double check the cam timing is correct?


SPYDER - 17/11/13 at 02:36 PM

If you've seen the injectors firing correctly then it has to be an ignition problem. Are six sparks present? And in the right order? If the components are OK when individually transferred to another car then concentrate on the bits that havent been swapped. VR sensor? Battery voltage sufficient? Can you record a log during cranking to see if ignition events are occurring correctly?


clairetoo - 17/11/13 at 02:38 PM

I have the cambelt covers off at the moment - all the timing marks line up - although with the exhaust cam being gear driven off the inlet its possible that the previous owner of this engine may have messed with it.......
I dont have a compression tester , but I do have a leak-down tester - gonna give that a try .


clairetoo - 17/11/13 at 02:43 PM

quote:
Originally posted by SPYDER
If you've seen the injectors firing correctly then it has to be an ignition problem. Are six sparks present? And in the right order? If the components are OK when individually transferred to another car then concentrate on the bits that havent been swapped. VR sensor? Battery voltage sufficient? Can you record a log during cranking to see if ignition events are occurring correctly?

It does spark on the duff side - I've tried the coil / leads on my car and it worked fine . I'm guessing the VR sensor (brand new) is OK since it starts with just the key , no throttle added .
The most puzzeling thing is the paired cylinders on the coil all work fine on one side of the engine - I've even tried swapping the injector loom over from side to side with no change .
Battery voltage - there is a charger plugged in while working on it - battery is showing 13.7 volts......


owelly - 17/11/13 at 02:51 PM

Timing 180° out on that bank?
Does Easystart make it fire?


clairetoo - 17/11/13 at 03:07 PM

quote:
Originally posted by owelly
Timing 180° out on that bank?
Does Easystart make it fire?

Its running wasted spark , and the other cylinders in the pairs run fine , which also rules out the coil and leads .
Just done a leak-down , and all six cylinders are within a few % (all between 25% and 30% )

I've got a can of easystart somehwere in the garage...........


jollygreengiant - 17/11/13 at 03:20 PM

It may sound stupid, but have you got a GOOD earth for the bank/set of injectors that are not firing. I had a similar problem with an injected pinto, had fuel, spark, compression just no running. Turned out to be A bad earth connection in one of the engine loom plugs.


clairetoo - 17/11/13 at 03:36 PM

The engine has a good earth - welding cable with properly crimped ends - and all the megasquirt earths are on the block .
All the possible faults I can think of would effect all six cylinders........


chrism - 17/11/13 at 03:53 PM

Only things I can think of are

knackered spark plugs on non working side

Bad earth for the plugs as said above, have you tried putting an earth directly to the head.

Head gasket gone so no compression on that side

Holed pistons on that side, although all 3 would be pretty unlucky.

Valves sticking open or bent if its an interference engine.

Compression test kits can be bought for not much and can I would say essential for setting up engines.


clairetoo - 17/11/13 at 04:08 PM

quote:
Originally posted by chrism
Only things I can think of are

knackered spark plugs on non working side

Bad earth for the plugs as said above, have you tried putting an earth directly to the head.

Head gasket gone so no compression on that side

Holed pistons on that side, although all 3 would be pretty unlucky.

Valves sticking open or bent if its an interference engine.

Compression test kits can be bought for not much and can I would say essential for setting up engines.


I've swapped plugs - side to side , from a warm , running engine , and even tried new ones.........

Bad earth.....theres two heads , both bolted to the same block and to each other - cant see that one happening

Head gasket or holed pistons.......leakdown test is the same on all six cylinders

Non-interference engine - with no bent or sticking valves , as proved by the leakdown test


mark chandler - 17/11/13 at 04:25 PM

Bad battery to the injectors on one side, megasquirt triggers by earthing the injector so trace back to the main relay.


big_wasa - 17/11/13 at 04:28 PM

When stripping an engine I ether put a rag or tap over any open ports. Nothing left in the inlet is there ?


rusty nuts - 17/11/13 at 04:31 PM

Have you got a vacuum port on the inlet manifold, a vacuum gauge is a very underrated diagnostic tool which will show up all sorts of engine faults.Loads of info on the web with diagnostic readings. By the sounds of it you have eliminated everything but the valve timing although similar symptoms could be cause by lack of tappet clearances


AdrianH - 17/11/13 at 04:38 PM

Not sure if this is possible with heads and plug angles etc. But, you have tried everything else.

Stick a piece of wooden dowel down the plug hole and with rocker cover off on one of the dead cylinders crank by hand and watch the dowel rise and fall work out when on compression stroke and put a timing mark on the crank a few degrees before TDC for that cylinder, then back together with a timing light check it is sparking at that point, you could even do it for all the cylinders to make sure you have a good even spread

Not sure what firing order you have out of the following, or even something different
1-5-3-6-2-4
1-4-3-6-2-5
1-6-5-4-3-2
1-2-3-4-5-6
1-4-2-5-3-6
1-4-5-2-3-6
1-6-3-2-5-4
1-6-2-4-3-5
1-6-2-5-3-4

You could even map them all out on the pulley, just a way of checking that gear you mentioned and checking it exhaust timing is doing as you would expect.

Adrian


theconrodkid - 17/11/13 at 05:08 PM

mainfold air leak ?,give a squirt of wd40 or similar around the area,have you got more than one TPS switch,one could be duff.


clairetoo - 17/11/13 at 05:12 PM

quote:
Originally posted by mark chandler
Bad battery to the injectors on one side, megasquirt triggers by earthing the injector so trace back to the main relay.

I've tried swapping the injector loom from side to side , it made no difference...........


mark chandler - 17/11/13 at 06:01 PM

Does the fuel rail circulate between all cylinders, try squirting some fuel straight into the inlet and see if that has any effect.

As you are running lost spark unless you have the firing order wrong it's highly unlikely to be the HT side, maybe a snapped camshaft on that side.


clairetoo - 17/11/13 at 06:15 PM

This is the engine I'm having trouble with........




Throttle bodies - so no manifold as such , the fuel rails are in series and the injectors are batch-fired .


davidimurray - 17/11/13 at 07:00 PM

If the fuel rails are in series could one be stealing fuel from the other? Is it the first rail bank that runs ok? How about popping both fuel rails out and pointing them into 6 containers to compare the amount the are flowing?


dave - 17/11/13 at 07:14 PM

Dont know the set up but have you checked the gap on the crankshaft pick up. My 4 cylinder MX5 only ran on 3 and i discovered that this was the problem. worth a try.


DIY Si - 17/11/13 at 07:17 PM

Only thing I can think of with these engines is misaligned cams on that bank. You've checked pretty much everything else!

Have you got the Mazda factory manual for the KL? If not, the alignment marks are on the head side of the sprockets, two dots that should line up. Only issue being that this means at least one set of valves is compressed, so it's a shite to do right first time.


Mr C - 17/11/13 at 07:20 PM

Are the correct trigger wheels fitted,, crank and camshaft??


clairetoo - 17/11/13 at 07:30 PM

The cambelt has been off , and back on again (replacement belt was wrong - damn ebay) , so cam timing was done with the cam covers off - easy with four hands (two to hold the cams in place with spanners , two to re-fit the belt and tensioner)
I have a spare engine in the garage , and the timing marks match the engine in the car .

I have a 35thou air gap on the crank sensor - too much ?


clairetoo - 17/11/13 at 07:36 PM

quote:
Originally posted by Mr C
Are the correct trigger wheels fitted,, crank and camshaft??

Its a 36/1 trigger wheel , fitted to the back of the bottom pulley with a ford VR sensor in the stock position




The whole setup is the same as my own V6 Mx5......but mine runs !


Norfolkluegojnr - 17/11/13 at 08:11 PM

Is the Ecu a known good unit?, I know it's wasted spark but maybe worth a check? Injectors clean? fuel rail/line not blocked? Signal at injectors correct?

Are you getting a spark on the duff side? Not sure if that's covered in earlier posts but I couldn't see it.

Spent ages fiddling with a tps sensor and my MJ only to realise the MJ was faulty.


perksy - 17/11/13 at 08:16 PM

Tried Noid lights at the injector connectors of the affected cylinders ?

Tested for a good spark at the affected cylinders ?

How did the Easy start fluid go ?




Sorry if already been asked, Just sped read the thread


clairetoo - 17/11/13 at 08:25 PM

I've tried two different megasquirts on it , and tried them both on my car - they work fine on mine , but just the three cylinders on this one .
I've lifted the fuel rail out still connected (cable ties holding the injectors in after firing one across the drive....) , cranked it over on the starter with a clean piece of cardboard under it - priming pulse , then regular squirts while cranking........and the plugs come out wet .

The sparks are a bit weak on the duff side - cant understand that , as when I put the whole coil and lead setup on mine it ran fine .


mark chandler - 17/11/13 at 08:29 PM

From the notes above

1 bank runs, the other is dead
It's running in batch mode so fuelling is not tied to crank position.
When you swapped the injection plugs over it made no difference, same bank still dead.
It runs wasted spark, as it runs on three cylinders timing cannot be an issue, it would be completely dead or run roughly on all cylinders.
You have substituted most of the bits from your known good car.

I had an XK8, if you flooded the engine it would not start, if you did manage to get it going on a few cylinders the others would not cut in, the fix was to take out all the plugs and dry, then squirt a little oil into each cylinder to maximise compression then it would start straight away.

Back to basics then and try and exclude stuff.

Plugs out, if possible replace with known good ones, squirt of oil in each bore and try and start with all injectors unplugged, just spray fuel into the throttle bodies working down each side.

If it is still completely dead on one side you must have got HT leads in the wrong order or something mechanical is amiss, waste spark proves the HT side.

Time then to whip off the cam covers and look for correct timing by lobe position and bucket gap to isolate possible bent valves.

On a separate note, it's a lovely neat install


clairetoo - 17/11/13 at 08:39 PM

Plugs.....I ran mine up till it was warm , then swapped the plugs and no change.......then put the `duff' plugs in mine , and ran them up to temp.......

Firing order has to be right - the coil and lead set works fine on mine ?

Checking cam timing by lobe position is tricky as it has contra-rotating cams , so they look wrong when they are right

And a leakdown test showed all six cylinders to near as dammit the same , so ruled out bent valves

[Edited on 17/11/13 by clairetoo]

[Edited on 17/11/13 by clairetoo]


mark chandler - 17/11/13 at 08:48 PM

The jaguar engines that suffered from poor starting were the ones with nikasil linings.

A quick google shows that the Mazda V6 also has nikasil liners, one if the first symptoms of failure of the nikasil lining is failure to start which you prove with a squirt of oil down the bore, also applies if the engine has not been started for a while.

It's because nikasil does not hold oil like a cast liner so you lose all compression, it will not start with cranking on the duff cylinders because the petrol washes the bore and makes things worse.

Squirt 10cc of oil in each failing bore, I managed to burn out a starter motor on my XK8 as I could not get it to start one day....... I thought the ECU must have gone until I learnt this trick.

Regards Mark

[Edited on 17/11/13 by mark chandler]


ashg - 17/11/13 at 08:51 PM

try increasing the fuel pressure. are you sure the return on one side is not starving the other? see if the bad side will run with the fuel blocked off to the good side.


clairetoo - 17/11/13 at 09:00 PM

The KL has cast iron liners - not very thick , but you can get +40 pistons so they are definatly re-boreable .


clairetoo - 17/11/13 at 09:02 PM

quote:
Originally posted by ashg
try increasing the fuel pressure. are you sure the return on one side is not starving the other? see if the bad side will run with the fuel blocked off to the good side.

Since the return goes to the FPR , the whole system has the same pressure - one rail cant be at a different pressure ?


Bare - 17/11/13 at 09:14 PM

Gasoline engines ALL require: fuel, air compression And spark to fire. Yours is clearly missing one of those elements
Do a compression test .. a Cheap tester is 'good enough'
Which cyls are linked on wasted spark?
Gawd! wasted spark is such a Mickey Mouse setup.. found on early 80's motorcycles, cuz it saved a few $ parts costs...basically.


02GF74 - 17/11/13 at 09:25 PM

quote:
Originally posted by clairetoo

Firing order has to be right - the coil and lead set works fine on mine ?




Is it possible it has different crank to yours so firing order is different?

can you turn the engine by hand and by watching the valves figure out the firing order?

this engine was a runner before right?

can your remove all plugs (to make it easier for engine to turn over) but for one plug on the dead bank and crank over - swap the coil pack to go through all permutations - one of them surely has to make the engine fire?

as you know, the cylinder on one bank fires follwed by its counter part on the other bank so the rods must share the same journal hence unlikely to be more than one variant of crank.

you definitely not got the duff cam 180 degrees out? it will give compression, no valve clash etc. but be on incorrect stroke... unless you are saying the waster spark takes place on the compression and exhaust stroke... in whcih case is something else. .





[Edited on 17/11/13 by 02GF74]


clairetoo - 17/11/13 at 09:34 PM

If the firing order was different to mine , it wouldnt run at all.........

And no , the engine hasnt run before (in this car) - but it has been faffing around on three cylinders for a week now
Untill it runs right I cant move on to finishing the rest of the car........


MikeRJ - 17/11/13 at 09:41 PM

quote:
Originally posted by Bare
Gawd! wasted spark is such a Mickey Mouse setup.. found on early 80's motorcycles, cuz it saved a few $ parts costs...basically.


Also found on millions of production cars...


snakebelly - 17/11/13 at 09:51 PM

You said the spark is a bit weak on the non firing side, surely that must be worth investigating, run a temporay earth to the head on that side to see if the spark improves?


clairetoo - 17/11/13 at 09:54 PM

quote:
Originally posted by snakebelly
You said the spark is a bit weak on the non firing side, surely that must be worth investigating, run a temporay earth to the head on that side to see if the spark improves?

I checked the spark by earthing the plug to the chassis.........


scimjim - 17/11/13 at 09:58 PM

In addition to fuel, compression and ignition, they need to occur in the correct sequence.

You have ruled out fuel, compression and spark - so I reckon it must be timing?

I know nothing about the KL but a quick google says that the cams are numbered? If you've not had it running, perhaps someone has put it back together wrong?

421 = Rear Inlet cam
431 = Front Inlet Cam
441 = Rear Exhaust Cam
451 = Front Exhaust cam (also has slots on the end for the distributor)


gallons perminute - 17/11/13 at 10:04 PM

Is this not the engine that the cam lobes are "pressed" in place over a tube? Sounds crazy but take the cam covers off and see if the lobes are actually opening the valves. A friend had this very problem with one bank of cylinders and it was because the tube that is the camshaft lost the fit with the lobes and as a result just turned.


clairetoo - 17/11/13 at 10:08 PM

quote:
Originally posted by gallons perminute
Is this not the engine that the cam lobes are "pressed" in place over a tube? Sounds crazy but take the cam covers off and see if the lobes are actually opening the valves. A friend had this very problem with one bank of cylinders and it was because the tube that is the camshaft lost the fit with the lobes and as a result just turned.

Not in this engine........cams are solid cast iron !
The engine certainly didnt look as if it had been apart , but if I pull the cam covers I'll check the right cams are in the right places .


owelly - 17/11/13 at 10:27 PM

I'm just trying to get my fuzzy sleep-deprived haed around this so bear with me....
The wasted sparks still need to be in the right place so iis it possible that they are in the right place on one bank, but not the other? Perhaps the TDC on the trigger wheel has been timed to the wrong bank. There should be a timing difference equal to the angle of the 'V'.
If that makes no sense just treat as if it was a response from Bare.


scimjim - 17/11/13 at 10:42 PM

BTW, love the install - followed your original thread all the way through! Just installing an mx5 engine into a Scimitar SS1, so you know where that logically leads to


r1_pete - 18/11/13 at 09:30 AM

Does this engine have VVT?

I had a problem a couple of weeks ago where the vvt was stuck 'advanced' and the engine turned over as if there were no compression. If the failing bank is stuck, it could be your problem.


hughpinder - 18/11/13 at 09:33 AM

You haven't got the live and earth wires on the injectors the wrong way round on that bank have you? Pretty much the only thing I can think of that hasn't been mentioned, and you would still get squirts of fuel out when testing - just at the wrong time for the cylinders to use it!
Good luck
Hugh


puma931 - 18/11/13 at 09:49 AM

I remember years ago trying to get a 944 to run, and it turned out to be a faulty reconditioned starter motor that was turning the engine over the wrong way! I am sure you have checked, but is the engine turnover over in the correct direction??


MikeRJ - 18/11/13 at 03:49 PM

quote:
Originally posted by hughpinder
You haven't got the live and earth wires on the injectors the wrong way round on that bank have you? Pretty much the only thing I can think of that hasn't been mentioned, and you would still get squirts of fuel out when testing - just at the wrong time for the cylinders to use it!
Good luck
Hugh


Injector polarity on electromagnetic actuated injectors typically makes no difference. Some injectors have the polarity marked as a simple diagnostic aid (i.e. so you can see which side is switched and which is ignition switched live), but internally the injector is just a simple solenoid so it's not sensitive to polarity.


hughpinder - 18/11/13 at 04:14 PM

You are right, I was thinking the magnetic field would be reversed so the movement would be, but that is not the case here.
Sorry about that.
Hugh


MikeR - 18/11/13 at 04:35 PM

As everyone has suggested everything else ......

is the exhaust clear on that side? No chance you've got something stuck in it / the gasket covering the ports? simple test is undo the manifold and give it a crank.

I do like the starter motor idea as I'm sure you have to swap it round to do your install.


clairetoo - 18/11/13 at 05:31 PM

Well - the starter motor is the right one for the V6 , and since it will start (on three cylinders...) I'm pretty sure its spinning the right way

The only thing I can think of , would too large an air-gap on the VR sensor be a problem ? Its about 35thou at the moment , and not too much of a mission to reduce it........


cs3tcr - 18/11/13 at 06:10 PM

I would check cam timing, get a degree wheel (print one off from the 'net) and a dial indicator. When I built the Coventry Climax for my last car, the bloody thing wouldn't run. Turned out that the cam in the Climax turned opposite to the crank and i had installed the cam thinking it spun the same way. I ended up printing out a degree wheel and recording when the valves opened and closed, which told me right way that the cam timing was way off.


rdodger - 18/11/13 at 06:15 PM

quote:
Originally posted by clairetoo
Well - the starter motor is the right one for the V6 , and since it will start (on three cylinders...) I'm pretty sure its spinning the right way

The only thing I can think of , would too large an air-gap on the VR sensor be a problem ? Its about 35thou at the moment , and not too much of a mission to reduce it........


If it's easy enough to move then I would try it. By the sound of it you have tried everything else.


MikeRJ - 18/11/13 at 07:29 PM

quote:
Originally posted by clairetoo
Well - the starter motor is the right one for the V6 , and since it will start (on three cylinders...) I'm pretty sure its spinning the right way

The only thing I can think of , would too large an air-gap on the VR sensor be a problem ? Its about 35thou at the moment , and not too much of a mission to reduce it........


Quite honestly I think it's unlikely that an incorrect air gap would only permit every other cylinder to fire.

Going back to your observation that the spark looked a bit weak on the non-operating bank I would check the coil wiring one more time. It's quite possible to wire up a wasted spark coil so that only one side works correctly (i.e. by connecting the 12v feed to the wrong terminal).

[Edited on 18/11/13 by MikeRJ]


perksy - 18/11/13 at 07:42 PM

quote:
Originally posted by clairetoo
I've tried two different megasquirts on it , and tried them both on my car - they work fine on mine , but just the three cylinders on this one .
I've lifted the fuel rail out still connected (cable ties holding the injectors in after firing one across the drive....) , cranked it over on the starter with a clean piece of cardboard under it - priming pulse , then regular squirts while cranking........and the plugs come out wet .

The sparks are a bit weak on the duff side - cant understand that , as when I put the whole coil and lead setup on mine it ran fine .





If the sparks are weak outside of the cylinder, When under compression they will fail completely.

Coil is definitely ok ??

Triple checked ALL circuit & coil connections & wiring ?


theconrodkid - 18/11/13 at 08:10 PM

If the sparks are weak outside of the cylinder, When under compression they will fail completely.

Coil is definitely ok ??

Triple checked ALL circuit & coil connections & wiring ?

as above.
try holding the HT cap a few mm from the top of the spark plug as that normally creates a HUGE spark and the engine should fire that plug.
that should yes/no the ignition system,as to why it is weak on one side.....watch next weeks exciting episode


rdodger - 19/11/13 at 06:57 PM

Any joy with this Claire?


clairetoo - 19/11/13 at 07:40 PM

I've not had a chance to look at it since Sunday - I woke up Monday morning with a rotten stinking cold and have just been keeping warm since then........
I dont think its the coil or firing order - I lifted the complete coil and leads off , connected them on my car , and it ran .
I cant find any more wires to double and triple check - the only thing I've not tried is reversing the wires to the VR sensor (I'm 100% certain its wired right , but with nothing left to try.........)


avagolen - 19/11/13 at 08:30 PM

So frustrating.

Spent a day trying to start a rebuilt engine in a Bond Bug once.
It would fire but never run. Towing it got the exhaust manifold glowing red....
Finally traced to camshaft / distributor drive problem. We had swapped the
distributor from the old engine which which went in the other direction. Had
To swap camshaft as well..

Not helping your problem though, just thought you might like a laugh. :-)


SPYDER - 19/11/13 at 11:48 PM

Isn't there a feature in some flavours of Megasquirt to log the trigger output? Are the VR's identical on each car?
My MS1 V3 has two trimmers on the PCB to calibrate the VR sensor. Has your ECU got the same trimmers?


mcerd1 - 20/11/13 at 09:25 AM

I know its a drastic step, but its sounding more and more like the the cams since you've checked nearly everything else and its affecting the whole bank.....

could the exhaust / inlet cams be swapped over ? (I don't know whats possible on these engines)

it might be worth taking the cam cover off just to check the actual valve timing


mark chandler - 20/11/13 at 06:03 PM

So is it working now ?


sjmatthews - 20/11/13 at 06:45 PM

Oh do tell


The Black Flash - 21/11/13 at 01:01 PM

I've come to this late, but I would definately guess at the cam timing. It's easy to get it 180 degrees out. I'd go with the "print out a timing wheel and check the timing with a dial gauge" approach. Or without a timing wheel, a stick down the plug 'ole on cylinder 1 to see roughly where TDC is.


v8kid - 21/11/13 at 01:23 PM

quote:
Originally posted by The Black Flash
I've come to this late, but I would definately guess at the cam timing. It's easy to get it 180 degrees out. I'd go with the "print out a timing wheel and check the timing with a dial gauge" approach. Or without a timing wheel, a stick down the plug 'ole on cylinder 1 to see roughly where TDC is.


+1 I hate cam timing it's so easy to get it backwards.

Cheers!


The Black Flash - 21/11/13 at 01:32 PM

Another thing - are you batch injection or sequential? If it's sequential, then check the wiring to the camshaft sensor - the wires could be the wrong way around, and there's no way to tell from. You just have to swap the wires round and see if it works.


clairetoo - 22/11/13 at 10:40 PM

Still not running

The cam and ignition timing are good - its got fuel pressure and working injectors - a leakdown test showed all cylinders to be near as dammit the same - and every electrical component works fine when tested on my car .

I did find one thing wrong on the wiring - the live feed to the coil was on the wrong end of the connector - but even with that sorted , it still only ran on three.......


mark chandler - 23/11/13 at 09:09 AM

If you disconnect the injectors on the bad bank, get it running on 3 then dribble some petrol down the TB's on the dead side and it picks up you have located as a fuelling issue.

Wasted spark with it running on one side, especially as you have tried swapping the leads around to no avail means you either have the firing order wrong on the bad side or it's mechanical, have you had the cam cover off and looked for a broken cam maybe ?

Although painful take both cam covers off and rotate the engine by hand and verify the firing order by cam lobe position and piston position, maybe a cam has slipped upon its pulley on the bad side?


GeoffT - 23/11/13 at 09:29 AM

Maybe as a further check on firing order you could remove all the HT leads on the dead bank and whilst it's running try each lead on all the dead cylinders in turn, just to make make doubly sure there's no combination that fires up the dead cylinders......?


clairetoo - 23/11/13 at 09:38 AM

I'll say this again.......its not firing order - I fitted the coil and leads (without taking the NUMBERED leads off) to my car , which is identical , and it fired up and ran fine .
Swapping anything around on the firing order just causes massive backfires through the throttle bodies .

[Edited on 23/11/13 by clairetoo]


MikeRJ - 23/11/13 at 10:09 AM

Which coil pack are you using?


r1_pete - 23/11/13 at 10:23 AM

How is the cam sprocket and gears keyed to the camshaft? it would be worth checking they are intact, and haven't failed, or been left out and allowing the wheels to move on the shafts.


rdodger - 23/11/13 at 11:22 AM

Claire. I think we need a recap and start again.

Have you had the engine running on all 6 cylinders using parts for your car?

Have you had your car running using ecu, coils, leads, plugs etc off Matts car?

On Matts car can you get both banks running individually by swopping the leads around?

You now have a strong spark on all 6?

All 6 injectors are firing? Do they fire at the correct time?


clairetoo - 23/11/13 at 12:03 PM

quote:
Originally posted by MikeRJ
Which coil pack are you using?

Ford coilpack - choice of four , all work on my car , none work on Matt's


clairetoo - 23/11/13 at 12:14 PM

quote:
Originally posted by rdodger
Claire. I think we need a recap and start again.

Have you had the engine running on all 6 cylinders using parts for your car?

No - apart from a few seconds when it may have , but it stops dead from several thousand RPM with no chance of catching it .

Have you had your car running using ecu, coils, leads, plugs etc off Matts car?

My car runs fine with any and all components from Matt's car .

On Matts car can you get both banks running individually by swopping the leads around?

No - and since its batch fired injection , and wasted spark , and tested working on both sides , dunno how swapping side to side would help (plus the loom comes in from one side of the engine bay and the coil is to one side , so none of the wires would reach .

You now have a strong spark on all 6?

Yes - but apparently only when the plugs are outside the engine........... Put a tested working plug in the engine , turn it over , pull it out wet and non sparking ten seconds later....

All 6 injectors are firing? Do they fire at the correct time?

All six fire - fuel rail removed from `bodies , engine turned over , fuel pulses from injectors as expected . Since theres now way of altering when they fire (plus as long as they fire , then they are fine) I have to assume something I cant change has to be right......



snapper - 23/11/13 at 01:10 PM

Run a separate earth from bad bank head to block
Yes I am also clutching at straws


adithorp - 23/11/13 at 01:13 PM

The more I read the more I think this is either...
1, A blocked exhaust (but that'd still fire even if just backwards/up the throttles).
2, Cam timing out due to a broken cam or sprocket moved due to a sheared key (but that'd probably fail the leak down).
3, Cam timing out 180' on that bank.

Have you done a compression check yet? It's not the same as a leak down. Have you checked the cam timing at the cams, not just the sprockets, with the rockers covers off?


theconrodkid - 23/11/13 at 06:40 PM

Yes - but apparently only when the plugs are outside the engine........... Put a tested working plug in the engine , turn it over , pull it out wet and non sparking ten seconds later....


so either a weak spark or too much fuel ?
try cranking with fuel pimp not running whilst someone squirts easystart or similar down the trumpets on the bad side ?


adithorp - 23/11/13 at 06:46 PM

quote:
Originally posted by theconrodkid

so either a weak spark or too much fuel ?



...or spark isn't on compression stroke.


avagolen - 23/11/13 at 07:29 PM

Hi Clare, you must be so frustrated with this.

Just re-read something Mark Chandler said earlier on.

He said the MS provides a ground for the injectors, which means they are fed with
what I assume is a common +12v.

The question is - if this is the case - is it a good +12v feed to the non running side.

If not, the injectors will not be allowing a good shot of vaporised, fuel just enough to wet the plugs.

Volt meter readings may show a good voltage when not running, but a poor joint will have high resistance
which in turn will give low current flow when required.

All the best.

Len


Pat_T - 23/11/13 at 09:02 PM

Claire,

I design & develop OEM motorcycle engines (including ECU tune development) and you have tried most the the things I would!!

One idea though:

Fault/voltage drop between the crank position sensor and the ECU?

We have issues where engines wouldn't start due to the actual ignition timing being some way removed from what the ECU thought it was doing.

Cam timing could be right, spark plugs could be firing, injectors could be pulsing, but if the sparks are not occurring at the correct ignition value you won't get anything.

The crank position sensor will work by being a certain gap from the pick-up (probably on the flywheel in this case?). Try moving it closer if you can - aim for a 0.5-0.8mm gap.

This will increase the voltage of the signal that the ECU sees during cranking.


also:
Can you confirm the static compression ratio is correct on that bank?

Edit - also try reversing the polarity of the VR/crank position sensor...

[Edited on 23/11/13 by Pat_T]


BaileyPerformance - 23/11/13 at 11:21 PM

are all 6 throttles opening at the same time?

are the plugs wet on the bank that does not appear to be firing? spit on the exhaust headers - are thay hot?

Do the exhaust headers get hot at all when you run the engine at 1/4 throttle? (does it pick up on the missing cylinders when you rev it? - open the throttle and rev the engine at over 2K for 20secs then check header temps again)


clairetoo - 24/11/13 at 09:41 AM

I did ask much earlier in this thread if crank sensor air gap could cause a problem - got no comments on that , so carried on checking and re-checking everything else........... I've just machined the mount down by another 10 thou , just gonna go and re-fit it...............

All the throttle open pretty much at the same time - well , as close as they can be set on a non-running engine.......

The `dead' bank is just that - three non-firing cylinders , that flood the plugs instantly (even went and bought yet another set of plugs yesterday)

Odd thing (to me) is that the spark at the plugs is very weak , but if you lift the plug away from the block , the spark will jump an inch , through the painted cam covers , it will even spark onto plastic trim........but earth the plug , and the spark is barely visible


owelly - 24/11/13 at 10:16 AM

Another thing I've encountered is faulty multi-connectors where the pins have pushed out through the block. Are there any that are common with the faulty engine?
I suggested a puff of Easystart earlier in the thread. Did you try this? This would help to diagnose if you were looking at a fuel or spark fault.


rusty nuts - 24/11/13 at 10:30 AM

quote:
Originally posted by clairetoo


Odd thing (to me) is that the spark at the plugs is very weak , but if you lift the plug away from the block , the spark will jump an inch , through the painted cam covers , it will even spark onto plastic trim........but earth the plug , and the spark is barely visible


Might be worth trying a larger plug gap .
As already suggested try squirting directly down the affected throttle bodies although I would use brake cleaner rather than easistart. Also have you checked the valve clearances, too tight can cause all sorts of problems,better to be slightly loose even if noisy


richardm6994 - 24/11/13 at 10:31 AM

Claire....sounds really frustrating.

The only thing can add is regards the vr sensor. I've currently got a problem on my megajolt setup where I randomly loose spark for a split second. I've not got to the bottom of this yet (it feels like I've tried everything) but during my investigations I messed about with vr sensor gap....
Mine is set at 20 thou and signals fine.....surprisingly though, it still works fine when I pulled it right back (bracket on slots) to 3/16" away from the trigger wheel.


rdodger - 24/11/13 at 10:39 AM

quote:
Originally posted by rdodger
quote:
Originally posted by clairetoo
Well - the starter motor is the right one for the V6 , and since it will start (on three cylinders...) I'm pretty sure its spinning the right way

The only thing I can think of , would too large an air-gap on the VR sensor be a problem ? Its about 35thou at the moment , and not too much of a mission to reduce it........


If it's easy enough to move then I would try it. By the sound of it you have tried everything else.


Has it worked?


clairetoo - 24/11/13 at 10:39 AM

So its not the VR sensor air-gap

It will tickover on three - as if the other side is not connected ? I tried putting a hand over the inlets - on the good side , it sucks your hand in and nearly stops........on the dead side ........nothing .
If anything , I can feel it pushing my hand away ? Maybe the cam timing is a problem , but externally looks good - the cam sprockets are bang on the marks .

Soon as I warm up (its piggin freezin here ) its off with covers , and dig out the workshop manual


mark chandler - 24/11/13 at 11:00 AM

Blocked exhaust will also give this symptom as the air has nowhere to go, if the manifold is easy to get at try knocking this off first and turning over, you never know when it was in storage it may have had some rags stuffed up the ports to keep everything clean.

Regards Mark


DIY Si - 24/11/13 at 11:43 AM

I'd go with turning it over on the starter with the cam covers off. One of the friction gears could be slipping/have slipped but the sprockets would still align.


clairetoo - 24/11/13 at 11:50 AM

Cam timing is spot on........I even turned the engine over slowly and watched the cams/valves doing their thing in the right order at the right time .
Everything that can be checked , has been - there cant be anything blocking the exhaust , its all new and built by me , and I know nothing was ever stuffed into it or any of the ports......it came off the welding bench and straight onto the car .

I'm gonna put it all back together , and try opening up the plug gaps - then maybe swap the injectors from side to side (but I doubt I've got three duff injectors all on the same side....)


MikeR - 24/11/13 at 01:32 PM

if you can feel it not sucking why are you thinking injectors?


clairetoo - 24/11/13 at 01:36 PM

quote:
Originally posted by MikeR
if you can feel it not sucking why are you thinking injectors?


Clutching at straws......................

I've pretty much had enough now - there is nothing more I can check or swap , and it still wont run .

The only part that hasnt been swapped is the engine........


MikeR - 24/11/13 at 01:44 PM

why not look at the exhaust side more. I'm far less knowledgeable than you but you seem to be missing the 'blow' bit.

another random idea, can you disable the side that works and try again. if its a volts / resistance thing that's too much with 6 cyls it could add another level of confusion if it works.

random musings of an ill person.


mark chandler - 24/11/13 at 05:32 PM

It should still suck your hand in even if not running, as you are satisfied that nothing was stuffed up the exhaust ports of the engine the only other reason I can think of is so much fuel has now washed the bores down that it has lost compression when cranking, a squirt if oil required in each bore required.

Although you have changed components you have not replaced the loom, if you have a short to earth in the cable header, the injector pins are opposite an earth then the injectors will stay fully open and flood the bank. It looks alright with a key of the ignition as you see fuel squirting. Mine now has a slither of plastic to separate the rows of pins.... Been there done that, got the badge.

You must be by by now with it

[Edited on 24/11/13 by mark chandler]


clairetoo - 24/11/13 at 06:23 PM

Yep - I'm starting to lose it

It cant be short on the plug - I've made a new injector loom , and tried it connected both ways.......if there was a fault , surely it would have swapped sides ?


rusty nuts - 24/11/13 at 06:27 PM

Have you checked valve clearances


simon cofield - 24/11/13 at 06:30 PM

Had exactly the same fault with V6 Isuzu engine....was a blocked cat on the none running bank...if you are running cats just remove exhaust manifold on the none running bank and try....won't cost anything to check!


clairetoo - 24/11/13 at 06:31 PM

quote:
Originally posted by rusty nuts
Have you checked valve clearances

non-adjustable hydraulic tappits........plus a leak-down test showed no leaking valves


wylliezx9r - 24/11/13 at 07:38 PM

This has got to be something to do with the weak spark. Can't you add another earth temporarily to that side of the engine using a jump lead or something ?

Can you Measure the voltage /resistance on the bad side of the engine block to battery earth (obviously both should be zero], I'm thinking maybe something has broken down to earth BUT would be surprised if it isn't affecting the other bank.

Otherwise I'm all out of ideas, best of luck


matt_gsxr - 24/11/13 at 07:39 PM

What did the compression test show?


DIY Si - 25/11/13 at 05:26 PM

I'd have a look at the idea of pulling the exhaust off the head and see what happens. As has been said, even a mostly knackered engine with little compression should still suck on the inlet unless it's blocked. On a similar note, I guess you've already checked that the inlets are clear?


steve m - 25/11/13 at 05:56 PM

I havn't any sensible comments to make, except have you tried your engine in the other car

Joke !!

But please get it running, soon, as I keep coming back to this thread, in the hope you have got it running, and I like a lot of others are baffled to why you can have 3 pistons firing, and 3 that do not,

I assume the 3 that don't fire are actually connected to the crank ?

Steve


jacko - 25/11/13 at 07:29 PM

I like Steve M keep looking at this post hoping you have got it running on all 6 cylinders good luck
Jacko


v8kid - 25/11/13 at 08:16 PM

Someone should start a book on the odds;-

camshaft - evens
Ignition 2-1 against
injectors - 10-3 against
misc wiring - 100-1

All profits to go to the locost site fund

Trouble is I know he haw about betting - what would you make the odds?

Cheers!


theconrodkid - 25/11/13 at 08:19 PM

If anything , I can feel it pushing my hand away ? Maybe the cam timing is a problem , but externally looks good - the cam sprockets are bang on the marks .

Soon as I warm up (its piggin freezin here ) its off with covers , and dig out the workshop manual



how are the cam sprockets held on to the cam,is the cam right relative to the sprocket ?.
as you are getting no suck on the bad bank,i think it must be cam timing or bore wash,if the cam is right with the sprocket,try some oil down the bores ans let it soak overnight ?


clairetoo - 25/11/13 at 09:06 PM

Finally got it sorted

Turned out the throttle bodies on the duff side weren't seating properly on the head - they had already been test fitted to another engine , but this one had a larger step on the gasket face machining..........so massive air leak on all three ports

Adapter plate now ground away everywhere it was touching , gasket re-coated , just going back on now !


adithorp - 25/11/13 at 09:11 PM

quote:
Originally posted by clairetoo
Finally got it sorted

Turned out the throttle bodies on the duff side weren't seating properly on the head - they had already been test fitted to another engine , but this one had a larger step on the gasket face machining..........so massive air leak on all three ports

Adapter plate now ground away everywhere it was touching , gasket re-coated , just going back on now !


You should know better than to tempt fate... wait 'till it runs before saying something like that.


rusty nuts - 25/11/13 at 09:12 PM

Nice one, glad you have it sorted


clairetoo - 25/11/13 at 09:31 PM

quote:
Originally posted by adithorp
quote:
Originally posted by clairetoo
Finally got it sorted

Turned out the throttle bodies on the duff side weren't seating properly on the head - they had already been test fitted to another engine , but this one had a larger step on the gasket face machining..........so massive air leak on all three ports

Adapter plate now ground away everywhere it was touching , gasket re-coated , just going back on now !


You should know better than to tempt fate... wait 'till it runs before saying something like that.


Fully re-fitted (had to warm my hands before finishing....) , and started first try - on all six cylinders !
Its a bit lumpy and poppy , but now I can get the `bodies properly balanced and tweak the ignition timing


sjmatthews - 25/11/13 at 09:39 PM

Great news, we'll all sleep much better tonight


avagolen - 25/11/13 at 09:47 PM

Excellent.


mark chandler - 25/11/13 at 09:51 PM

Phew..........


rdodger - 25/11/13 at 09:53 PM


steve m - 25/11/13 at 10:18 PM

Phewwww

like 10000 others I can sleep at night now


Norfolkluegojnr - 25/11/13 at 10:38 PM

Breath no longer baited. Well done!


The Black Flash - 25/11/13 at 10:52 PM

Good stuff . Interesting how it was something that nobody was even close to guessing. They've always got a surprise up their sleeve.


mcerd1 - 26/11/13 at 08:18 AM

I bet your relieved now

quote:
Originally posted by The Black Flash
Interesting how it was something that nobody was even close to guessing.

theconrodkid guessed right on the first day
but I'm guessing that however big the leak was it wasn't that obvious or claire would have found it sooner...


hughpinder - 26/11/13 at 08:22 AM

Thank goodness, it's been driving me mad.
Well done
Hugh


The Black Flash - 26/11/13 at 03:05 PM

quote:
Originally posted by mcerd1
I bet your relieved now

quote:
Originally posted by The Black Flash
Interesting how it was something that nobody was even close to guessing.

theconrodkid guessed right on the first day
but I'm guessing that however big the leak was it wasn't that obvious or claire would have found it sooner...


So he did, I didn't see that even on re-reading!


mysmallwheels - 30/11/13 at 05:44 PM

Claire and others,
Once upon a time, long long ago, my 16 year old self put his first v-8 together. The god of combustion smiled down upon this child innocent, and the v8 sort of roared to life. Sort of because, like Claire's v6, only one bank was running and not well.
This led the innocent but stubborn child on a great adventure for about 3 months; Finally convinced mechanic friend to have a look; no joy! Three days later he called me and suggested I turn it over with the valve covers off, where I could see the right bank valve spring s were not compressing as much as the left. The Mechanic then asked me just how far I had torn engine down, then told me I likely had a bad gasket or otherwise blocked oil feed to the lifters. Unfortunately, with my innocence shattered, I learned he was right, I had put the head gaskets on the wrong sides and blocked 75% of the upper right gallery and the HYDRAULIC lifters never got sufficient oil to properly open valves. This adventure scarred me in ways that have taken me years to get over; I often read manuals and material on jobs I've done many times, fearing that I will screw it up!
Very glad this sorted ! I'll add only that a piece of 10mm hose, a meter or so long, makes a great leak probe: place one end by your ear(not innit !), and move the other end by all the places vacuum could leak; when you hear something akin to soup strained thru a mustache you are on it! This trick was courtesy of the Mechanic, who overhauled his first motor in 1921, so it's an "oldie but a goodie".
Much Luck on All, MSW, Chris