I recently purchased a 2000 Sunfire GT with 138,000k, and have experienced the few problems others have had in the first day I got the car.
I noticed that the fan does not work in the settings 1-3, and looked at the wiring diagram, to figure that it was the blower motor resistor. It was fairly simple to figure out, because the 1-3 settings only go to the resistor, where the 4th setting is a parallel circuit to the blower motor. So the blower motor will always have power in the 4th setting, whether or not the resistor is working.
The other interesting problem, is the fact that the stupid reminder beeper for the 'keys in ignition' doesn't shut off when the key is in the accessory position. So, in other words, I can't listen to the radio when the car is off without that annoying beeping in the background. The interesting thing, is that I think that the dome light problem I'm having might be related to this as well. I'll have to see what I find out in the wiring, door switches, etc.
Whenever the car is on, the dome light and reading lights in the rear-view mirror are on... until you start driving, and they decide that it's a good time to turn off. When I stop the car, they will sometimes come back on. I have been able to find the "sweet spot" where the reading lights won't stay on, but I had to take the dome light right out of the car for now. Let's just say it's not a fun thing to happen at night while driving. So I'm not sure what the problem with all that is, but I think that it might have a similar source. We will see soon enough.
I had the check engine light come on too. I went to the shop where I work and checked the codes. It was: "p0420" catalyst efficiency low bank 1. So that directs me to the first 02 sensor or the Catalytic converter.
I am taking it back to the dealership to have these few problems fixed, however, I think that I will end up doing the majority of the repairs, because they probably won't want to fork out the money. I did not purchase the hugely overpriced warranty that they had offered, because I feel that I would rather fix problems myself. At least that way I know that they are done right (I am a young female mechanic). So I now see that I am in for a lot of electrical troubleshooting with this car.
The trunk latch totally sucks too. I am going to have to either modify this one to fit tighter, or replace it so that it stops rattling every time I go over a speed bump. The rear seat latch is also not doing anything to hold the seat in place. The part where the latch is supposed to connect with the 'hook' isn't even lined up. I really wonder about the previous owner sometimes... This one escapes me. I will simply adjust it or replace it.
I discovered that I have to bypass the immobilizer and disable the airbags to install my after market CD player. I just hope that my massive stereo (2000W, 2X 12" dual voice coil competition subs @ 1ohm mono) won't be setting off the airbags while I'm driving!!
So if anyone has already done some of this before, all comments are welcome before I go get dirty playing in the wires. Contact me @ firstname.lastname@example.org only if you are serious about informing me or asking intelligent questions.
I very patiently await the long list of repairs I will be completing on this car. Despite all the weird things that have gone wrong, it isn't much different from any other manufacturer's defects in workmanship that I've seen. I like the little thing and can't wait to be rid of these inconveniences. *Sigh* I suppose that I have my work cut out for me, I just hope that I won't have all these other problems that everyone else is having with the DRL and fuel pump etc.
OK everyone, safe driving!