Intermittent Miss fire 172

[497adam]

Hi my 172 has developed a bad miss fire, this morning was fine for about half a mile (engine just starting to warm) then it came back. Its quite a bed miss. Any ideas?
Its had plugs (correct ones), magnecor leads and lambda in the last 8k and other than being due an oil change is fully serviced up.
What are your thoughts guys?

 

[497adam]

coil pack ? or does create a constant miss fire?

 

[CuppyDean]

Coil pack or an injector issue

 

[497adam]

oh also, engine light came on but cleared when re-started?

 

[497adam]

could this still be coil pack? and am i best getting genuine one?

 

[497adam]

?

 

[CuppyDean]

Pm maynard on here he will sort you out with a coilpack, he works for gsf

 

[497adam]

the none genuine ones ok?

 

[497adam]

?

 

[maynard]

We stock OE Valeo and Beru one's. I'll drop you a pm first thing in morning.

 

[497adam]

Borrowed coil pack to try not cured it

 

[Iceberg_172]

Injector circuit possibly! with the car idling, unplug them one at a time, if the car struggles even more when you unplug one then that one is working fine. If nothing changes then its that injector circuit giving you hasstle. Do this with all 4.

By circuit i mean it doesnt have to be the injector itself, it could be a broken wire or something, to eliminate this, swap the faulty one with one that works, the problem should have moved to the cylinder you placed the faulty injector in. If its still on the same cylinder you took the suspected one from, the problem is with that circuit.

 

[497adam]

Thanks for advice guys, off to birchdown shortly (if i make it) just havent got time this week to try and sort it. but if the 2 kevs cant sort it this afti will have to get stuck in on sat

 

[trind]

Mine had the same issue was the crank sensor, gradually got worse so may be worth a check!