Hello once again fellow Holden owners I am having a problem with a rough idle, definitely sounds like a missfire but the computer comes back with fault code 12 which means the computer isn't registering any missfires. I have replaced Leads and spark plugs. i have used some injector cleaner. I think my inlet manifold is leaking as under my coil packs there is lots of black dirt that seems to be getting onto the belts and spinning oil all around the engine bay, if needed i can get some pictures so you guys can see and try help me. This problem is only when idling or when just taking off and not pressing the accelerator. such as when coming to a complete stop or moving off the idle is so rough that the exhaust under the car is bouncing around and making a noise. The car has always had this problem as long as i have owned it but it does seem to be getting worse. I dont seem to be losing any oil or radiator fluid. The idle
Compression came back all good. All the spark plugs look the same. When unplugging each injector there was one that made absoluteness no difference to the idle when unplugging it. So gonna buy a new one and see how it goes.
