iceviolet 0 Posted November 20, 2008 Hi, this is a strange one. Travelling to work yesterday and the car was running fine, after 15minutes or so driving, stood ad the traffic lights the car nearly stalled and then ran very rough,lots of vibration and missfiring, hard to accelerate and constant missfiring. Did it again on the way home, same again after 15 minutes or so, ran perfect in the first fifteen minutes. Same again today. took all the plugs out,cleaned them and they looked fine really. started the car and let it run and again after about 15 minutes it nearly stalled an running rough and lumpy on idle and missfiring when revving and lots of vibration. Its very strange, like turning on a switch, gets warm after about 15 minutes then just runs like ive described. Has anyone come across this before and know what it is?? Thought about the coilpack but why would it wait 15 minutes before deciding to play up?? Plugs seem fine. Ive plugged the car into vag-com and the only code it came up with was oxygen sensor - intermittent, could this be a possible explanation for this?? cheers Quote Share this post Link to post Share on other sites
ADZ_VR6 0 Posted November 20, 2008 i had a broken wire on my oxegan sensor just after the filter wich made it run lumpy but it was all the time. take it off make sure theres no dirt or anything there.??? Quote Share this post Link to post Share on other sites
PROVR6 0 Posted November 21, 2008 Ive got a similar thread going, but my problem is nowhere near as bad as what you describe. Someone suggested it could be a duff or failing cat. Is yours good? Quote Share this post Link to post Share on other sites
dr_mat 0 Posted November 21, 2008 Engine sensor most likely. During the first while from cold start it's on the cold start map, and pretty much ignoring the lambda/maf. Check the error codes on the ECU first. Quote Share this post Link to post Share on other sites
PROVR6 0 Posted November 21, 2008 Where is the engine sensor location? Quote Share this post Link to post Share on other sites
iceviolet 0 Posted November 21, 2008 Well im going to have a look at and probably change the lambda sensor this weekend and see if it solves the problem. Quote Share this post Link to post Share on other sites
dr_mat 0 Posted November 21, 2008 I meant *an* engine sensor, this sort of thing could be caused by a few of them. Scan the error codes before randomly changing parts. Quote Share this post Link to post Share on other sites
iceviolet 0 Posted November 22, 2008 Well had a play around this morning cleaned connections to the lambda and MAF, took coilpack off and cleaned that up too. Had it plugged into vag-com and the lambda signal looks fine, hovering around 1. So i dont think it is that, and the MAF works i think,unplugged it when car was running and it definatley changed the running. My brother thinks it is the coilpack. Im going to get a new one and try it, the one that is on, is the original bosch one by the looks of it, date stamped 1993. So hopefully it is this. The only thing that makes me think it might not be is the fact it is fine until the engine warm?? Anyhow will post up the findings when ive changed it. Quote Share this post Link to post Share on other sites
iceviolet 0 Posted November 23, 2008 Ive got a similar thread going, but my problem is nowhere near as bad as what you describe. Someone suggested it could be a duff or failing cat. Is yours good? I have no idea if its good? how do you tell?? It just sailed through the MOT last week. Anyhow I went for a short drive just now and the symptoms are the same. I have also just noticed that when i got home and turned the engine off, the usual ticking you get from the exhaust and cat cooling down was there but also some very loud ticks and cracks. suggesting its got hotter than normal, so i had a look under the car and noticed that the cat was glowing red! is this normal?? Quote Share this post Link to post Share on other sites
PROVR6 0 Posted November 23, 2008 Cat could be clogged causing unburnt fuel to make it glow hot. This could be caused by a faulty lambda sending too much fuel (although yours seems ok), old spark plugs, sparking in the wrong order. Id deffo get it checked out if its glowing as you don't want a fire starting. Quote Share this post Link to post Share on other sites
iceviolet 0 Posted November 23, 2008 Yea i will have to get it checked out. Yes the lambda seems fine and the plugs are virtually brand new! I swapped over the cam sensor today aswell with another one i had just to eliminate that! Hopefully the new coil will solve my problems, should get it tuesday or wednesday. Quote Share this post Link to post Share on other sites
iceviolet 0 Posted November 25, 2008 Problem solved!! It was the coilpack. Managed to get a Bosch one for just shy of £125, so wasn't too bad. Runs like a dream now, smoother on idle and also seems to start quicker too. The cat doesnt glow now either! Was thinking about getting a de-cat anyway, are they beneficial at all?? Quote Share this post Link to post Share on other sites
steve @ 0 Posted November 25, 2008 Problem solved!! It was the coilpack. Managed to get a Bosch one for just shy of £125, so wasn't too bad. Runs like a dream now, smoother on idle and also seems to start quicker too. The cat doesnt glow now either! Was thinking about getting a de-cat anyway, are they beneficial at all?? If your engine is pretty standard then not really no. Quote Share this post Link to post Share on other sites
