Hi I was hoping someone could give me some advice about this prob. I have a 98’ new shape 1.6 16v Astra sport. When I start it with the engine warm, say if its being sitting for a couple of hours it misfires, its fine cold, its fine hot. This misfire lasts for a couple of mins and then clears itself, the first thing I did was to change the spark plugs for some GM ones, but this made no difference, the plugs I pulled out look fine as well, and there was no sign of dampness around the coil pack.
I have been told that the prob is carbon building up on the inlets valves causing them to stick, the car has covered 70,000 miles, is this a correct diagnosis, and apart from pulling the head off is there any treatments I can use to remove this carbon?
No it doesn't rattle, it doesn't have a dizzy cap or leads, it just has a coil pack directly above the plugs. I checked this over and it doesn't seem to be damaged in anyway. About the ECU, if the light goes out as normaly whilst this problem is occuring, do you think there will be any codes stored on it even though the light isn't on?