I previously replaced the cabin air filter, I thought this had fixed the problem, but as soon as the weather got really hot the air conditioner started doing the same as before, hot air then cool for a while then warm again, I had the refrigerant checked everything looked fine. so I took it back to my dealer, I told him to check the cabin air temperature sensors, because of the intermittence of this AC. They finally caught this AC in the act of blowing warm, then cool then warm, . The cabin air temperature sensor was showing that the cabin was way to cool (even though it wasn't cool enough) and would open the temperature control door to allow heat into the cabin to warm it back up. (example the inside temperature setting on 70 deg. actual inside temp about 80 deg. but the temperature sensor thinks its 65 deg. so it tells the temperature door to open.to heat the inside up.) Anyway, there are two cabin temperature sensors an upper and a lower. I had them both replaced. the parts are about 20 bucks each. but they are not easy to get to so it may be three or four hours labor involved.

2012 Buick lacrosse Air Condition was not cooling properly, It would blow cool for a while, then blow warm, then cool again. It never would cool the passenger compartment down to the desired temperature setting. Passengers were complaining about it being hot in the car. I took it to the Buick dealer, the mechanic couldn't find anything wrong. Still on hot days( temperature above 90deg.) the A/C wouldn't cool the passenger compartment down to a comfortable level.

The air coming from the vents wasn't cold all the time, just sometimes for a few minutes. then warm.

I checked the inside cabin air filter, sure enough it was choked up, I could not see any light through it when I held it up to the sun. I replaced this filter for about 10 bucks. This cured my air conditioner problem on my Lacrosse. This filter is located behind the glove box. The glove box has to be removed to get to it, I guess that's why the mechanics didn't check it, because it takes a few extra minutes to remove this filter.

I reported this issue to FC Kerbeck Pre-Owned and New Dealership my first summer after purchasing my vehicle. My first experience the AC blew out hot air. I had all fluids check everything was okay. Still blew out hot air. I took my vehicle back to FC Kerbecks for maintenance concerning the air conditioning unit not working. Returned in a few days AC was working, however you had to turn the AC up to 6 in order to feel the air. I returned back to FC Kerbeck with a concern the air wasn't cold enough the blowers felt blocked because I had to turn it up to 6.

In addition when the air conditioning is on and running when it is time for me to turn off the AC then turn off my vehicle, sometime it would start and sometimes it did not. My neighbor also has a Buick Lacrosse and she haves the same issue. Right now my air condition is not working again for the second year, and my neighbor's is not working.

It is very ironic that the same make and model vehicle owned by two separate people are having the same issues. This is very frustrating; I informed FC Kerbeck to contact the manufacturing company at GM to notify them of this issue. I have not received any notification indicating this issue was ever sent to General Motors. My car is still under factory warranty but my neighbor’s car is not and so many others are not. General Motors need to recall these vehicles and fix this issue; it creates an unsafe environment if you become stranded.