Hi guys,

So I’ve been hunting a potential fuelling issue but I don’t think it is fuel any more.

Taken a quick video, does this give any clues as to what’s going on?
https://youtube.com/shorts/A9XFequPBf8?si=Onm5E27xFZi7FPWW

FUEL
Cleaned out all filters, replaced lines, getting around 3.2bar from the pump on idle, goes up to around 3.5-3.8 under load.

SPARKS
Checked spark plugs and gaps which all look good
Maybe there could be a coil issue?

AIR
Suspecting a potential air leak have been checking all round the intake but can’t see any obvious signs of a leak.

Any thoughts appreciated!

Thanks
Andy

That sounds like electrics to me
Spark plug or plugs , ht Leeds , coil pack that’s what I would look at
G

Stick a new set of plugs and leads on. We've had dozens of zetec misfires we've cured that way, despite not seeing anything obviously wrong with then.

Thanks guys, just ordered new coil, leads, and sparks.
Will get them fitted tomorrow and see what happens!

Check there is spark at each plug

Ok so a bit more detective work this morning, no spark on cylinder one.
Have tried new sparks, leads, and coil but hasn’t made a difference.

Any idea what would cause just 1 cyl to not fire?

My next plan is to check wiring between the coil and ECU, and then if no signs of trouble then maybe it’s the ECU itself?

[Edited on 10/5/25 by pekwah1]

Are you running an electronic control module (ECU such as OMEX etc) with injectors or are you on carbs

It's wasted spark, so if cylinder 4 has spark, cylinder 1 should have spark as well as the trigger wiring is shared between the 2 internal coils in the coilpack.

Normally the spark missing on a wasted spark pair would indicate an internal short to earth in the coil (the usual failure point on the ford coilpack), being missing with all new components is a bit odd though.

Try swapping the plugs/leads between 1 and 4 on the coil to see if that moves the missing spark, it won't affect the running and if the missing spark moves it is down to the plug/lead.

My striker's apart at the moment due to a misfire that turned out to be more serious, I had valve recession on 2 cylinders causing a loss of compression on 1, weirdly on the inlet valves with no damage to the seats.

It didn't loose much power, but had a cold misfire that faded away after 3-4 mins running, it wasn't even spitting back, just a bit hesitant at low rpm, so came as a surprise when I stripped the head.

Dave

Ok turns out I was being dumb - didn’t have cyl4 lead connected which is why I had no spark on 1.

So all 4 have got spark but still not running right.

It’s on standard Ford ECU.

I’m starting to wonder if the engine has given up
Does this sound bottom endy to you guys?

https://youtube.com/shorts/yLql-_9GS5Y?si=wVX2rdWDuI-D3Y3k

Loose tappets. Or valve problems ?

Maybe a compression test is needed
G

If you are running a CAT then be careful of driving it with one or two coils out. I nearly burned my Fury to the ground as the cylinders without spark will be pumping petrol, straight into the exhaust and can then burn in the exhaust and CAT. The Exhaust on the Fury is in a fibreglass pod which does not help, a seven may be safer but may kill the CAT.

Compression test and note readings
(Make sure you do it with wide open throttle)

Is it worse when the engine in hot or cold?