Intermittent stutter

[S15AK]

Got a intermittent stutter/misfire problem, not sure what it could be. Plugs have been changed, service only just done, its been mapped this year so all in good health. However ever now and again if I go for a quick launch, so build up the revs and go for it in first, the engine seem to bog down and start to stutter, if I lift of then give it the gas again it seems to be OK. It has only done it once or twice if I've down shift at speed and gone for it.

I have splitfire coils so doubt it could be them, so anyone got any ideas? I hate intermittent faults

Cheers

 

[Chriscooke]

Check the plugs are still tight. Mine did this for a while before firing a plug out the top of the head

 

[S15AK]

yeah plugs are tight, it started doing it even before I changed them over for new. It seems spark related though, but not sure how.. Only way is I suppose it to start swapping looms, plugs, coil packs about to try and pin point it. For the amount of times it happens not sure its for the hassle.

 

[fez06]

Put old plugs back in and see if it goes could be a faulty plug

 

[meddler]

can you put the standard coils back in? I know you have spitfires, but you never know. It's something you can definitely cross off the list.

 

[S15_SAM]

Have you done a compression test or leak down test?
Could be 02 sensor being that intermittent?
Afm too?

Who mapped the car, as may be worth asking them to check their map?

 

[S15AK]

yeah its all been compression tested, I had a boost leak problem (I changed all the boost pipes for SFS hoses) and I went through all that, so its had a clean bill of health engine wise.

It was originally mapped by FC tuning, but after the boost leak it needed doing again so Jez and H-dev did it, as I was in his neck of the woods at the time. Its not a place I can just pop back to either

 

[S15AK]

The old plugs were knackered, they took a battering going to LeMans and back so they needed replacing anyway. I can go down the route of swapping out the coilpacks, but as it only dose it now and again it might be hard to re-create it..

I think its done it before though even before all the re-maps, so thinking it might be the loom or even the splitfires as Meddler says as they have been the only constant thing.

 

[spec-rs15]

Mine does the same but just driving normal will start to stutter back off a touch then feed it again and comes good this is just around town driving , I found it if I start the car and let it warm up to temp.first its ok but if not it gets the bogs could be coolant temp sensor being stupid ?