1 cylinder not firing when but not coil pack or plug

Possibility of bent or sticking valve. Do a compression test? I had this on another engine type . It ran perfectly when cold but only misfired when hot.

JB

It's pretty likely to be the injector, we fitted loads on Fiats - the Brava HGT was a common one (which has the same engine).

If the light is on then a quick check on a code reader should confirm the fault.

Insider knowledge wins the day again. Bloody sight easier to do an injector than an inlet valve too I'd reckon :>)

JB

*cough*

Fuckit.

Thanks for the advice.

I did a compression reading on it 6 months ago and everything looked fine, the problem has started recently though.

Can the ecu tell the differnce between a failing coilpack/plug and an injector fault ?

I'm just thinking that having the code read at a dealer will cost £40 quid min when I can fit an injector myself no probs...

Anyone know how much an injector will cost ?

Cheers

Stoopid...

Usually, yes.

It could be cheaper than guessing!

About £90 each.

Try swapping the injector on number 4 with one of the others. That should tell you whether it's the injector or some other fault. Mike.

Move injector 4 to another location and see if the dead cylinder also moves!!!!

Do the same with the coil pack.

This will narrow it down to HT / Mechanical / fuellign problem.

Tim..

Quite an echo we have in here. Mike.

I'm not complaining two answers is better than none :)

Andy Hewitt wrote: >>I'm just thinking that having the code read at a dealer will cost £40 >>quid min when I can fit an injector myself no probs... >

Fair point. Though I'll try swapping the injectors first as it might save me a trip to Fiat to get the code read.

Bummer, more than I thought, better make sure I diagnose it right then.

Thanks guys

Stoopid...

I'd be tempted to get one from a scrappie (and maybe soak it in injector cleaner before use) - odds are that a crashed car wouldn't have had duff injectors!

Yeah I'll be trying that first, there's not many 20vt coupes (ie none) in the scrapys up here in sunny Scotland though :-(

Update on the fault finding:

I now measured the resistance across all the injectors when the symptoms are happening and guess what...all read the same 18ohms, which ties in with the Fiat workshop manual figure, except the one on the problem cylinder.

Now where's that yellow pages...

Cheers

Stoopid...

Yes, although you may still need to go there to get the code cleared, and the light extinguished.

Yes indeed.

St00p!d wrote: > Update on the fault finding: >

Although the fault with logged in the permanent memory it'll flush out after a 100 or so successfully starts.

The light goes out straight away when the problems clears which is good :)

Cheers

Stoopid...

Yup, at an average of 2 a day it'll be gone in a couple of months :-)

It does, but can leave the system somewhat unstable on a Fiat when fault codes exist.

Hi All

Thought I'd update you on my progress:

Managed to get a set of five injector 2nd from a low miler and had them cleaned which improved the flow rate a bit :-)

Fitting them has cured the problem which is good too.

There's a small but though, although the car runs fine now it seems to be slightly slower at catching when starting, I'll see if it settles down...

Cheers

Stoopid