Hello, I have a 1999 chevrolet blazer which is located overseas in Europe so I can't bring it to my trusted mechanic here in the states. The issue I am having is as such, The Blazer has about 87k miles. I just recently put a new AC compressor on since the last one had a small leak. I just had the system recharged. The issue I am having is after turning on the car, the ac will blow cold air into the cabin with no issues, then after a bit of driving, I will get bursts of warm air coming through the vents for a short period of time, usually a couple minutes at a time and then it switches back to cold usually relatively quickly. This happens over and over again and its very intermittent. I believe the AC compressor shuts off during the warm air periods. I do not understand what's going on with it and any help would be appreciated. I was told by the mechanic that I brought it into that there are no leaks.

 

The first thing that you need to determine is if the compressor is turning on and off or if this is a vent control issue (blend door/recirc door). If the compressor is turning on and off then the refrigerant charge may be low (low side switch), the pressures may be climbing high (high pressure switch) or a malfunction of either switch. The compressor or clutch can also be failing.

Was the system evacuated, the accumulator/desscicant changed and the metering device changed or inspected/cleaned?

Was care taken to ensure the correct amount of oil during the changeover?


George