the ac on my truck quit blowing cold air u can hear the compressor kickin on and off like it is surging. sometimes it will come on and stay on if you keep turning it on and turning it off. now it wont blow cold at all. any ideas?

 

start with the simple stuff, i would try adding a little bit of R-134a, sounds like you have a low charge

 

I bought a compressior off of an 03 to go on my 06 six the salvage i bought it form said it would work the mechanic i get to put it on says it wont work. any ideas would be great.

 

Mine was pretty similar to your symptoms, worked when it wanted to. Then began to blow warm and only warm. Had the R134 recharged and nothing changed. Just took it to the dealer today and got the bad news...Evaporator and Condensor leak...so if your R134 levels get too low your compressor has a safety feature which shuts it off to prevent it from burning up

 

well I just got a compressor off of an 03 put it on and it is cooling now. my mechanic says he takes them off 03 and 04s and puts them on 06 bc there is a relay on an 06 thats under the fuse box that goes bad and the 03 doesnt have the relay