ac
 

The AC in my 1998 AMG C43 cuts out after runing about 30 minutes or so. It is ice cold when working, but it cuts out with no warning and will not go back on unless one turns off the car and re starts it after one or two minutes off. The refrigerant pressure is fine and there is no other apparent problem. The dealer wants to replace the whole system at $1500!!

Thanks for your help.

mgomez
Not sure about your car, but for my car (1992 300TE) the symptoms would fit to a compressor switch off due to speed differences: If compressor speed is lower by 30% or more than engine speed the clutch disengages and only resumes after an engine restart. Could be something as trivial as a loose and slipping serpentine belt. Or could be a compressor that starts to seize.
Regards, Bruno

The new systems don't match rpms.

You should first look to an actual value implausibility. Press and hold the rest button till the display changes. Click the auto buttons each side to run through the numbers. Number five is evap temp. The first few numbers are temp sensors and if tested first thing in the morning they all should be the same (before running the car).