2004 Pontiac Grand Prix A/C help....

[mhilton11]

My 2004 Pontiac Grand Prix A/C is acting up. Sometimes it works great and other times it wont blow at all or gradually go from nothing to working as i drive. I have been told to replace the resistor. Is there anyway to test the resistor to see if that is my problem?

[mhilton11]

Just found out that if its not working and I slam the passenger door it kicks on and works great until I hit a bump (railroad, pot hole, speed bump).....Ha!!

[Larry Jr]

might see if the flapper door under the dash is operating correctly, some are electric, some are vaccuum

[Faster7]

The fan always blows, but the temperature is what changes? Or is the fan slowing down or shutting off?

If it's just the temperature but the blower fan is always working as it should, I'd look at the compressor clutch: the coil could be getting week and/or the air gap could be getting a bit big.

[mhilton11]

The temp stays cold. Its the fan that goes from blowing hard to blowing nothing and repeats. Replaced resistor and didnt help