Any help on this problem would be much appreciated, it's driving me and a fair few others mental!!
Right then, here goes.............................................
I have a 51 plate Astra Coupe SE1 2.2.
I had it in for a cam chain change around 18 months ago (under a recall), car went in fine, work was done, but when I picked it up, I was told it was running 'a little lumpy'. I never thought anything of it at the time as they told me it would clear up (why did I believe them )
I should have returned the car, but at that time I was in no position to do so, so I just put up with it.
The car runs fine for the first 3-4 minutes after starting, then the lumpiness begins. Under load the engine is perfect, no lumpiness at all. If I sit at idle and hold the revs at 1000 the lumpiness disappears as well. The car has stalled on the odd occasion if left idling .
I have just recently had the car in at a local garage and they have absolutely no idea what is wrong! They sent the car to a Vauxhall dealer who had it for 4 weeks and couldn't fathom the problem either.
I have read the sticky on the forums, but believe what is mentioned there has already been done. I don't have a full breakdown of all the work carried out but what I do know is.............
Throttle body inspected/cleaned
EGR valve replaced
Numerous sensors replaced (seems like all of them!!!)
Inlet manifold gasket replaced
2 different ECU's tried
No faults are showing on the diagnostic machine either. Vauxhall stated their next step was to remove the head!
All this has happened after the cam chain change, the car was perfect beforehand.
Sorry for the long post!
Any input greatly appreciated.
ps I've been told the timing is correct, but not sure they actually did check?