I am having a problem with my ac. When I'm driving the ac stay on and blows ice cold, but when I come to a stop the qc goes warm and sounds like the compressor turns off and back on over and over and the car wants to stall out. I am having 2 codes po107 and po171 could those be the problem with the ac problem?

 

I'm thinking it's all related. First thing is to identify which car you have? 2000-2004 1.9L or 2004.5-up 2.4L or 2.5L S40?

On the 1.9L engines the P0107 code is the MAP sensor on the intake manifold. Not the one on the air-air heat exchanger (up by radiator) but the one attached to the intake manifold. The P0171 is probably a result of the MAP being off and giving the engine incorrect information. The a/c compressor cycling on and off could be the car's computer reaction to a low idle speed. Personally I'd get the MAP fixed first, clear the codes and see if they come back. My .02

 

I Have the same problem, 2004 Volvo S40 1.9 turbo. the A/C turns off when the car get hot, the level of the temp gauge is more than middle, I change the thermostat, radiator, check hoses and water pump and everything looks OK. But the car runs for 10 minutes and get hot and turns off the A/C. I check the piston compression and looks fine. No codes, only the temp sensor and I put a new one. I don't find a temp sensor that have in the center console, that the only thing I don't change. But the car steel getting hot after 10 min. and turn off the A/C. I don't know what to do. Need urgent help.

 

When the engine is hot is both the top and bottom radiator hoses hot to the touch? Have you tried running the car without the t-stat installed?