My 92 300sd has a/c that works intermittently. First start of the day, it may take an hour or longer for the compressor to engage. If the car is sitting at idle, I will notice the rpm dip each time the compressor trys to kick on. Once it is on, it's fine until I turn the car off. Any suggestions (other than leaving the car running all day)would be appreciated. I have been warned about the potential a/c problems with these cars.
Best regards.
Tim

 

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