I bought a 1995 SL320 last week with 61K on it. The air was cold last Saturday and Sunday but today it was almost hot. Any idea why the sudden change? The compressor was kicking in when i hit the Economy button.

 

charge it and add dye to the system. then have it checked for leaks or see if your leaking under the car where evaporator water drains out for traces of dye, on the left and right sides of the ransmission. very common on your car is the evaporator which goes bad and needs replacement. few thousand $$ to replace. but check for other ac system leaks first.

 

I had simular problem with it blowing warm air instead of cold on automatic. the dealer stuck me with a misdiagnosed bad climate control unit. turned out to be the cabin temperature sensor in the dome light assembly. If it's the evaporator you should be getting ambient termperature air coming out not warm air. also check for oil around the drain hose for the evaporator, compressor oil can leak out there too indicating a bad evaporator. if the evaporator needs replacement, the dash has to come out, so it's very labor intensive. if you do have it replaced, replace the heater core while you're in there. don't want to go back in there again down the road cause labor will be around 12 hundred plus.