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Author: Subject: Another megasquirt problem.....
clairetoo

posted on 12/5/08 at 07:20 PM Reply With Quote
Another megasquirt problem.....

I have had a bit of help getting my car to start and tickover - but now things are getting serious
The car is virtually finished so I have gone ahead and booked an MOT for saturday morning and need to get it driveable in a hurry
I have fitted an LC1 wideband controller and gauge , and have just spent 1 1/2 hours trying to get the AFR to a sensible level , but now if I touch the throttle it coughs/spits and dies - it wont move forward under power aithout dieing .
Can any one help ? I have been trying to figure out `autotune` but cant find any reference to it on megatune ?





Its cuz I is blond , innit

Claire xx

Will weld for food......

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paulf

posted on 12/5/08 at 08:23 PM Reply With Quote
Hi Claire good to hear you at least have it running. To use autotune it needs to be at least driveable gently on the road but is really of limited use. To tune it properly it needs to be adjusted manually and then datalogged using the Megalogviewer software which when set correctly does a very good job of adjusting it.
However you need to get the base settings correct before you can use it, you will need to have the req fuel, temp settings,O2 settings etc set correctly and a good stable idle etc.
You then drive it with the laptop connected to record the run over a varied slection of roads and speeds,then run the program and it gives a suggested new map which you load and do the same again along with manually tweaking if required.Repeat this a few times and a usable map results.
Paul

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the_fbi

posted on 12/5/08 at 08:48 PM Reply With Quote
quote:
Originally posted by clairetoo
but now if I touch the throttle it coughs/spits and dies

TPS setup properly?

I presume MS knows when you're at idle and has a few different parameters set, is the TPS letting it know you're not at idle properly?

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mark chandler

posted on 12/5/08 at 08:56 PM Reply With Quote
Start with the suggested MAP, autotune will just drop everthing to zero, best ignored.

First off take out your temp senders, water and air, measure the resistance value in ice cold water, then add as much boiling water again and measure (50 degrees), then drop in biling water.

Now using megatherm adjust the internal table.

Next with Megatune:

Go to
settings
VE table
tools
VE specific
Generate table

Stick in your variables.

Now try using this as a base map.


Regards Mark

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clairetoo

posted on 12/5/08 at 09:06 PM Reply With Quote
quote:
Originally posted by paulf
Hi Claire good to hear you at least have it running. To use autotune it needs to be at least driveable gently on the road but is really of limited use. To tune it properly it needs to be adjusted manually and then datalogged using the Megalogviewer software which when set correctly does a very good job of adjusting it.
However you need to get the base settings correct before you can use it, you will need to have the req fuel, temp settings,O2 settings etc set correctly and a good stable idle etc.
You then drive it with the laptop connected to record the run over a varied slection of roads and speeds,then run the program and it gives a suggested new map which you load and do the same again along with manually tweaking if required.Repeat this a few times and a usable map results.
Paul

Thing is............without an MOT I cant drive it.............if I cant drive it I cant get an MOT..........
As it stands I dont have the faintest idea how to make it drivable enough to get to the MOT station and pass the emissions test
And to use autotune , you allso have to know how to use autotune.......I cant find anything to do with it on megatune ?
Whats `datalogged using the Megalogviewer ` ? .......... I have no idea what any of that means - sorry





Its cuz I is blond , innit

Claire xx

Will weld for food......

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clairetoo

posted on 12/5/08 at 09:09 PM Reply With Quote
quote:
Originally posted by mark chandler
Start with the suggested MAP, autotune will just drop everthing to zero, best ignored.

First off take out your temp senders, water and air, measure the resistance value in ice cold water, then add as much boiling water again and measure (50 degrees), then drop in biling water.

Now using megatherm adjust the internal table.

Next with Megatune:

Go to
settings
VE table
tools
VE specific
Generate table

Stick in your variables.

Now try using this as a base map.


Regards Mark

Both temp senders are reading right - and I have had a few hundred tries at using the table generator but without knowing the power and torque figures it dont work - just keeps telling me the figures I`m putting in are wrong.........





Its cuz I is blond , innit

Claire xx

Will weld for food......

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paulf

posted on 12/5/08 at 09:53 PM Reply With Quote
You need to guess at the power and torque figures to enter or maybe try a google for a rough idea , the map generator should then give some figures it may run with to start out.
Paul.
quote:
Originally posted by clairetoo
quote:
Originally posted by mark chandler
Start with the suggested MAP, autotune will just drop everthing to zero, best ignored.

First off take out your temp senders, water and air, measure the resistance value in ice cold water, then add as much boiling water again and measure (50 degrees), then drop in biling water.

Now using megatherm adjust the internal table.

Next with Megatune:

Go to
settings
VE table
tools
VE specific
Generate table

Stick in your variables.

Now try using this as a base map.


Regards Mark

Both temp senders are reading right - and I have had a few hundred tries at using the table generator but without knowing the power and torque figures it dont work - just keeps telling me the figures I`m putting in are wrong.........

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clairetoo

posted on 12/5/08 at 10:04 PM Reply With Quote
quote:
Originally posted by paulf
You need to guess at the power and torque figures to enter or maybe try a google for a rough idea , the map generator should then give some figures it may run with to start out.
Paul.

The problem with that is - I have a rough idea of power/torque figures and RPM`s , and I have tried every variation I can think of......and it just wont work





Its cuz I is blond , innit

Claire xx

Will weld for food......

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paulf

posted on 12/5/08 at 10:06 PM Reply With Quote
Just had a look for power figures, try 140 bhp and 115lbs torque, you will need to guess at the revs but something like 6000 max power and maybe 4500 max torque might work.
Paul.
quote:
Originally posted by clairetoo
Both temp senders are reading right - and I have had a few hundred tries at using the table generator but without knowing the power and torque figures it dont work - just keeps telling me the figures I`m putting in are wrong.........

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mark chandler

posted on 12/5/08 at 10:14 PM Reply With Quote
If its a 3litre then try this: Rescued attachment claire.JPG
Rescued attachment claire.JPG

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clairetoo

posted on 12/5/08 at 10:15 PM Reply With Quote
tried that - it says `Torque at maximum HP (122.5) is higher than at peak torque (115.0)!`

If that makes any sense to any one

Off to bed now...





Its cuz I is blond , innit

Claire xx

Will weld for food......

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mark chandler

posted on 12/5/08 at 10:21 PM Reply With Quote
A quick fiddle, this one works. Rescued attachment claire2.JPG
Rescued attachment claire2.JPG

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clairetoo

posted on 13/5/08 at 05:31 AM Reply With Quote
Um...........but as my engine isnt a 3 litre making 220bhp would the map generated work ?

[Edited on 13/5/08 by clairetoo]





Its cuz I is blond , innit

Claire xx

Will weld for food......

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omega 24 v6

posted on 13/5/08 at 07:49 AM Reply With Quote
Interesting thread this one. In particular the "how can I run it if I don't have an MOT"
I'm getting close to that stage myself and thinking HTF am I going to manage??
Best of luck to you.
Is it possible to get a ve table at say various engine speeds up to say 3000rpm just by sitting in the garage/driveway with no load i.e. just by gently building up the revs of the engine to an extent where it will be at the proper AFR for a noise test at the required revs?? obviously it won't run on the road like this as there is no load on the engine. presumeably thats where the accel enrichments etc kick in. You'll also need to be able to run it up to speed for a speedo check which will be a bit more challenging. I'm hoping myself that i may be able to "borrow " a bit of private tarmac if needs must the only trouble being that its totally flat. Still it should be enough at least to get to sva. Failing that it's a rolling road session which IMHO could be a hit or a miss finding someone who can work with/understand megasquirt AND EXPENSIVE





If it looks wrong it probably is wrong.

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MikeR
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posted on 13/5/08 at 11:58 AM Reply With Quote
Daft question - you know what your engine did new from the factory, couldn't you use those as the starting points?

I know it will be wrong, but its got to be better than a complete guess.

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DaveFJ

posted on 13/5/08 at 12:36 PM Reply With Quote
I was/am in the same boat.....So from one novice to another......

When I had my SVA last thursday I was faced with a 100 mile round trip in a car that won't even idle smoothly!

But it made it and passed the emmissions/noise test easily!

I took the very basic (generic) VE and spark tables from the megasquirt maps site and then 'fiddled'

I know my config is currently cr*p but it runs enough to get about....

I think the secret is in getting a good smooth idle (which i haven't)....

once you have got the idle reasonable then download mega log viewer from one of the various sites... then let the engine warm up before starting a datalog and revving it a bit (if you can drive it about at all that will help). switch off the engine and then open up mega log viewer. load the datalog file you just created. there is then an option to analyse the log file and you can then save the results back to a map that can then be uploaded back to the megasquirt...

crap explanation but it may help

EDIT>>>>>

Wqas thinking about this afetr i posted and realised i hadnt asked the obvious question....

have you looked on www.megasquirtmaps.com for a basic map for your setup to get you started? there are loads of maps on there for various setups...

HTH

[Edited on 13-5-08 by DaveFJ]





Dave

"In Support of Help the Heroes" - Always

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darrens

posted on 13/5/08 at 06:17 PM Reply With Quote
Hi Claire

Anyone who fits megasquirt in right from the start (as I did) faces this conundrum.

On certain engines, the options of Injections per cycle and Staging can make a vast difference. I found that "alternating" and 4 squirts suited my engine. Where-as simultaneous was just un useable.

If you start with a standard base VE map, you must adjust your reg fuel (not VE table) and engine constants to acheive a good idle (set the AFR to start with quite rich, around 13.5-14). Set your tpsdot very high i.e 20 ish, in the EGO setting Controller Auth needs to be 0 to avoid any WB corrections. IGNORE Autotune until you have it running reasonably. Perfect emissions can be easily setup with a WB without autotune.

If you achieve a good idle (that restarts OK), then you can adjust your VE table around idle to achive the the AFR you require.

This should get you driveable, drive/tractability i.e smooth progression surging can be sorted out later, Megalogviewer is an excellent tool for sorting your VE table (but will ONLY be as good as your AFR table). I found that even after using Megalogviewer, although the car drove OK, I still got loads of surging at various load areas. This was completely eliminated by viewing the VE table as the 3D map in Megatune ("Tuning/Fuel VE Table 1) use the arrow keys to smooth every section of the map, this will remove harsh transitions and big VE jumps, this also applies to your advance table (if your using spark).

Hope the above helps, fuel injection programming of anykind is a huge learning curve, it's taken me awhile to be completely happy with the tune, but by the end of it, the reliability and capabilitiy as fab.

Cheers

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clairetoo

posted on 13/5/08 at 09:12 PM Reply With Quote
I did finally get the `table generator` thingy to work last night ( just couldnt sleep till I did it ) but it was so late I wasnt able to try anything more in the garage - and I`ve spent tonight bonding in a new screen so no computer/engine time
But now all that is left to do is get it running well enough to get that MOT so I will try a few of your suggestions tomorrow - and my MOT man is cool with me plugging the lappy in to get the emissions right if needed !

[Edited on 14/5/08 by clairetoo]





Its cuz I is blond , innit

Claire xx

Will weld for food......

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Jenko

posted on 14/5/08 at 10:41 AM Reply With Quote
I found the Table estimator a total and utter waste of time, it was not even close with me - Every thing came out too rich (by a lond way).......
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clairetoo

posted on 14/5/08 at 03:29 PM Reply With Quote
quote:
Originally posted by DaveFJ

have you looked on www.megasquirtmaps.com for a basic map for your setup to get you started? there are loads of maps on there for various setups...

HTH

[Edited on 13-5-08 by DaveFJ]

Yep - looked and asked - but no one seems to have fitted a megasquirt (let alone throttle bodies and a coil pack) to an Mx3 - it seems to be a bit of a first !





Its cuz I is blond , innit

Claire xx

Will weld for food......

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chriscook

posted on 14/5/08 at 07:20 PM Reply With Quote
The table calculator only 'works' if you are running speed-density (map sensor for load) you are running alpha-n (TPS for load).

You might need to increase your acceleration enrichments. Have you tried very slowly opening the throttle to see what it does?

Did you sort out your different AFRs of each side of the engine?

EDIT- Oh it was CO that was different wasn't it. Can you put the Lambda sensor in either side?

[Edited on 14/5/08 by chriscook]

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clairetoo

posted on 14/5/08 at 08:53 PM Reply With Quote
quote:
Originally posted by chriscook
The table calculator only 'works' if you are running speed-density (map sensor for load) you are running alpha-n (TPS for load).

You might need to increase your acceleration enrichments. Have you tried very slowly opening the throttle to see what it does?

Did you sort out your different AFRs of each side of the engine?

EDIT- Oh it was CO that was different wasn't it. Can you put the Lambda sensor in either side?

[Edited on 14/5/08 by chriscook]

It feels like acceleration enrichment needs upping a bit - not too sure how to do that but I`ll have a good look tomorrow .
Unfortunately I cant try the lambda sensor in the other side as the way I`ve fitted it would mean a fair bit of work
But auto-tune seems to be doing something as it will now pull a bit of load without dieing - and it seems to have stopped smoking on the left side as well ( now that I`ve been able to rev it a bit............ )





Its cuz I is blond , innit

Claire xx

Will weld for food......

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Jenko

posted on 15/5/08 at 01:16 PM Reply With Quote
Ideally, you should not be playing around with AE until tick over is happy, and the surrounding VE cells are approximately ok....
You really need to know what your AFR is doing, if you are too rich, the adding AE will make matters worse......


You mention autotune, Are you trying to use the Lambda sensor to change your AFR?....If so, again, you should first be getting a half decent base map before doing this, otherwise the AFR correction will be trying to work too hard.......

We really need some AFR numbers for tickover, and light revving of the engine (not under load)......this will tell if you are in the 'ball park'......


Next time you can spend time on the car, use the time to get your datalogging working....this is the key to solving any of the problems.....
You can post files on here and we can diagnose everything from the logs....

As an example you will see graphs like the ones attached......Unless you have this facility working, then you have very little chance of getting the car up and running to get you to an MOT station.....



Paul. Rescued attachment Graphs.png
Rescued attachment Graphs.png

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Steve Lovelock

posted on 15/5/08 at 01:59 PM Reply With Quote
You could book an MOT at a station that is miles away for say mid afternoon then spend a day driving to it testing and changing the data as you go. Then when you get near you can turn round and drive back. If stopped you can say that you have an MOT booked and that the car is not running well enough to pass so you are bringing it back home to sort the problems out.

Maybe not the most ethical solution but I would have thought it would stand up legally.

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