How to test the coils is in techinfo. Rusted posts on the coils (usually just one) is fairly common. Clean it off well with emery cloth or steel wool, then apply dielectric grease. Clean up the plug wire also. Personally, when they corrode like that, I eventually just replace them.
Well I went to the dealer and had them read the code that just came up:
DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient
He said this would make it run like it is. He was able to manipulate the computer to make the problem worse and 'better'. He said the EGR is good so it may be just carboned up. I am going to clean that out later. Should I get the gasket for it? I am thinking yes, but do not know if I could get away with it. I think I am on the homestretch!!!
AHHA!! I have found my problem. I removed the EGR and cleaned everything out, reassembled and started the car. No fix. I had the can of carb cleaner and the one spot I never tested when looking for vacuum leaks was the flexible tube that connects the EGR to the manifold. I remember putting that back on and wondering if it cracked. Apparently it did! I sprayed that and the idle went all to hell!! I am going to check out alldata and find a part number for this. Does anyone know where I can get one. I know you guys that are always taking you car apart deal with this Thanks alot!
I went ahead and ordered the part from GM. I wanted to use GMpartsdirect but by the time you pay shipping, it is the same price as the dealer I smell a conspiracy :P Anyway, when I do this, do I have to remove the throttle body again? If I do, since I just replaced the gasket on the TB, do I have to replace it again?