Cylinder 1 occasional misfire - plug and coil OK - where to look next?

vendredi 24 octobre 2014

For about 3 years now, my 2005 KJ has had an intermittent misfire on cylinder 1. The plug and coil have been replaced twice, but still the problem recurs.



There's no specific trigger that I can discern. One day the CEL will come on, I'll pull the codes and it'll be P0300 and P0301. I'll reset them and the CEL will stay off for a while - at one point last year, it stayed off for over 1500 miles of driving - but usually it'll be back within about a week, which equates to about 200 miles.



I never actually notice the misfire, and the engine seems to be running as smoothly as it ever did, apart from a slightly lumpy idle (which may just be down to a dirty IAC motor - it's never been cleaned since the Jeep was new). If I don't bother to reset the code the CEL will eventually go off by itself, which I guess means the problem hasn't recurred within the last 50 key cycles.



So... any suggestions of where to look? I'd like to nail this one permanently if possible, but obviously such an intermittent fault could well be extremely difficult to run to ground.




0 commentaires:

Enregistrer un commentaire

 

Lorem

Ipsum

Dolor