Random misfire

[The Beardo]

ok so the scum run mobile has developed an annoying misfire! Car ( 172 ph2) starts up an idles fine, will drive fine for about 2 miles then develops a misfire on 1 or 2 cylinders! If you turn the car off and leave for an hour to cool down it starts fine again, suggestions please ?

 

[bloke]

eml? codes?

if not crank sensor or if it is down on two then coilpack/signal wire/ecu. you'd have to be bloody unlucky for it to be ecu.

 

[adamlstr]

I had a lead once upon a time that once it got any kind of warm it started misbehaving.

 

[The Beardo]

eml? codes?

if not crank sensor or if it is down on two then coilpack/signal wire/ecu. you'd have to be bloody unlucky for it to be ecu.

Don't have a code reader to hand, so can't check at the moment.

 

[Mr Plums]

When i had a misfire only when the car was up to temp, it was my top inlet that wasnt nipped up tight, im guessing when it was hot it expanded causing a slightly larger air leak, nipped it up properly and it went away.

 

[oVerboost.]

Could be your pre cat lambda... runs fine til it switches from the cold start map