jkesselring

Hi gang,
I have been having some issues with my 86 305 TPI Iroc (auto). The car has been running rough, throwing about every code in the book. The car idles rough and seems to miss just off idle and when you areall stand on it at high speeds it seems a little slow to gain RPM. The car cruises great at high speeds but seems to miss a bit at 35-45 or so. The tach even twitches a bit. The biggest question mark is that all of the cylinders show 210 psi cranking press with very slow leakdown, all of the plug wires seem to check out okay, and all of the plugs are perfectly tan, but the #3 plug is BLACK (I changed plugs and a week later it was black again - after only driving 100 miles or so that week). It isn't oil, but it looks a bit damp to be carbon, maybe carbon and gas mixed? Bottom line is that everything seems fine and looks good except this plug that keeps going dark. What would cause this? Injectors? They all check out at 15 (7 of them, #3 included) to 16 ohms. Could it be the EGR or its control solinoid? I am at a total loss, conventional engine wisdom seems to be being thrown out the window. PLEASE HELP ME!!!!!!!!!

Guest

Hows the spark on that cylinder? Thats the question I'd be asking first. Second is the injector.

Oh yea, you said its throwing every code in the book. Check your engine ground, especially the grounds at the back of the cylinder heads, they might be loose... or worse yet, not connected.