I have a 99 Grand am with a p0301 misfire problem. I have tried to fix it and am not having any luck. I have replaced plugs, coils, coil housing, housing grommets and ignition module. The problem is still present. I have cleaned the throttle body and put high end chemicals throught the fuel system, still no luck. The weird thing about the issue is that it really only happens when it is cold or the car is cold like first thing in the mourning. If the car sits all day in warm weather it drives fine like nothing is wrong. I have thought of a number of things to try, but I don't want to keep throwing money at it. If you can help in any way please email me. Thanks

Welcome to AF!!

One thing you didn't change were the plug wires. They are one of the week links in the system and account for most misfires. If you have changed the wires then the next item is the injector itself. Pull the one from cylinder #1 and place it in the next one to it, if the misfire changes then the injector is bad and needs replaced.

I would say however, this problem is with a plug wire though. One thing I suggest is to use extra dielectric grease on the boots both at the plugs and at the coils. Also make sure your plugs are properly gapped.