Doof 11 Posted July 4, 2006 Since driving to birmingham a few weeks ago in the extreme temperatures we had I seem to have a problem of misfiring but only when the car is hot. I drove from Nottingham to Cambridge the other night when it was cooler and she was fine all the way, happily revving away, 1 hour and 30 drive and I didn't notice a single miss. Driving from work last night to a karting track I got stuck in traffic and the water temperature started creeping up, still about 2 notches from red so nothing to worry about. Anyway i got out of the traffic and onto a clear A road where i opened it up to 80-90 and it was misfiring like mad. Sometimes it loses almost all power, sometimes it just misses enough to kind of rock the car forwards and backwards while on constant throttle, almost like a limiter would feel in a high gear. I'm convinced this is related to temperature but can't think what it could be. I changed the dizzy cap and plugs at the weekend too which doesn't seem to have done anything. Also, unrelated to this, I had a listen under the car while it was idling and theres some horrible rattling from the sump. I took it out after this and after warming up took it to the limiter a couple of times....it didn't blow up. If these noises are coming from the bottom end, should a few blats up to the limiter kill it...thus proving that maybe the noise isn't coming from the bottom end.......or something? Cheers for any thoughts, Lewis Share this post Link to post Share on other sites
SweetBadger 94 Posted July 4, 2006 Not sure what to make of the missfiring at higher temp, but if your oil pressure is ok the rattling is more likely to be coming from the gearbox input bearing. Try getting someone to press the clutch while the car is in gear and see if the rattling goes away. Share this post Link to post Share on other sites
Fuqa 0 Posted July 4, 2006 hey doof ive seen this on 2 occassions.. one turned out to be the faulty dizzy and one was found to be a faulty coil Share this post Link to post Share on other sites
Doof 11 Posted July 4, 2006 Cheers for the answers guys. I'll have a listen and lunch with the clutch down whilst in gear. Interestingly my gearbox does seem awfully ropey these days with regular crunching and lots of whineing....least it sounds straight cut I'll get posting a wanted ad for a coil and dizzy, cheers Fuga. Share this post Link to post Share on other sites
jackherer 543 Posted July 4, 2006 as its heat related I'd look at the ignition amp, it may just need some new thermal transfer paste so it can keep itself cool. Share this post Link to post Share on other sites
Fuqa 0 Posted July 4, 2006 as its heat related I'd look at the ignition amp, it may just need some new thermal transfer paste so it can keep itself cool. yup that too Share this post Link to post Share on other sites
Doof 11 Posted July 4, 2006 Not sure what to make of the missfiring at higher temp, but if your oil pressure is ok the rattling is more likely to be coming from the gearbox input bearing. Try getting someone to press the clutch while the car is in gear and see if the rattling goes away. Fantastic SweetBadger! As soon as the clutch was depressed the noise went away....interestingly this could be related to my gearbox starting to crunch recently. Is this bearing you are talking about the one that pushes against the clutch to activate it? I'll be sure to check out the ignition amp for the misfiring, thanks for the replies guys...gotta love this forum Share this post Link to post Share on other sites