Wy wife has a 1986 SL560 and lately has been having AC problems. A couple of weeks ago, she was driving the car (on a hot day) and heard a loud bang. She stopped immediately and we had the car taken to a shop we use. The mechanic said one of the AC hoses burst and replaced it. The car did fine and the AC worked normally for about a day. then the ACbegan toblow out less cooler air. After a bit, it would get cool again and then start warming up. At times, it does not cool at all and now even when some cool air comes out, it is not very cool.

We have taken it back to the shop twice. The first time, he made an adjustment. I am not sure what (my wife took the car and I was out of town)he did but it fixed it again for about a day and then the same symptoms returned. the second time, he checked everything and could not find the problem. However, he says it might be a sensor.

Any ideas?

 

The symptoms read like a failing/failed monovalve. Kits to repair are very inexpensive. Ask your tech if he checked this component as part of his diagnosis.

Bob

 

Thanks so much Bob. I'll run that by the mechanic and let you know what he says.

 

Forgot to mention...

If you turn the temp wheel to the MIN setting so that it 'clicks' in place, and the AC then cools, then it's almost certainly the monovalve.

Bob