So I have had my 07 base model ls2 for about 2 or 3 months now, and when I first got it, the AC was working fine, but it also was not hot outside like it has been lately. My AC works intermittently, but it seems to have to do with engine RPMS, air temperature, or air flow. When I first get in the car in the morning the AC will work and the compressor will kick on, then it will slowly start blowing warm air. Sometimes going down the road if I put load on the engine, the AC compressor will kick back on and start blowing cold air, or if I rev the engine up. I have checked the freon, and it appeared to be normal, I tried adding some, and then I tried removing some, and neither of those worked. I have also replaced the AC pressure switch, and it is still doing the same thing. I am about to take it to the dealer, or a local AC mechanic, but I wanted to see if you guys had any suggestions on what might be wrong? I am very mechanically inclined so I would rather fix this problem myself if possible. The problem is something is causing the AC compressor to not turn on, because when it does turn on, it blows cold air and everything is fine. I read it will cost me upwards of $1500 to have the dealer or a shop replace the AC compressor, not sure if that is true or not.

The car does have a vararam intake, and I have read that that can block airflow and cause AC issues. I do not have a stock intake to swap it out to see if that is the problem.

At this point, is my best option to take it to the dealer or a local mechanic and get them to tell me what is wrong with it, and then decide if I want to tackle the project myself? or maybe I should just let them fix it, I do not have a shop to work in and I have limited knowledge in AC.

Thanks

 

Take it in to the shop.

It could be a simple problem like your Freon not in the correct pressure range (read too high and when it over pressures as it heats up, will kick the system out), or could just be a bad connection at the compressor clutch or the clutch going out instead.

The clutch is easy enough to test, and all you need to do is put 12v on it, and make sure that is locking in to drive to compressor.

The clutch is easy enough to pull and repair/replace on the compressor without having to pull the compressor or even drain the Freon, but if you don't have the tools and talent, not something that you want to take on yourself.

http://www.ebay.com/itm/like/321186314104?lpid=82&chn=ps&ul_noapp=true
As for it its the clutch, the shop will just want to replace the entire compressor isntead. Hence reclaim the Freon, replace the compressor with it new clutch, then put a vacuum on the system to draw out any moisture, and then recharge it with Freon.

Also to point out, it could be something easy and stupid instead, like your cabin temp sensor just popped loose, and instead of clipped into the gauge cluster bezel, laying in the bowels of the dash isntead.

 

Most problems can be found by looking at error codes - I'll bet you have some.

 

Hey all,,
Just wanted to provide an update. Took it to a local shop and had him checkk it again. It turns out we had VERY slow leak at the low side shrader valve stem. Couldn't tighten it at all so we replaced, vacuumed and charged it and it is still holding. been about 2 weeks now with no issues. thanks for the advice and help as well.