Hey all! New to the forum and a new Pontiac owner myself. I have a 2002 Grand Prix GT with a rough idle issue that is starting to get on my nerves, but before I buy all the sensors the code reader requires, I thought I would see if any of you had a similar problem and had a different fix to it.
Here is what is going on:
At start-up, it revs high, then falls to around 500 RPMs and continues surging about 300 RPMs around idle. Occasionally, it will die.
When coasting to a stop, it will surge about 500-600 RPMs. When it is under a load, or driving normally, say with the cruise control, it runs perfectly.
Here is what I have done so far:
Replaced MAF sensor as asked to do by code. Code still shows up when reading them even after replaced, but indicated low voltage to the sensor. This helped out the issue, but didn't resolve it.
Replaced PCV valve (it was stuck)
Cleaned EGR valve (It was sticky)
Here are the codes:
P0102
P0135
P0141
P0443
I also have some wires between the valve cover and the firewall that are not hooked to anything. It is a 3 prong connection, part of it runs down to the o2 sensor. I am not sure if it goes to anything because I have nothing to compare it to.
Cheers!
Walt
