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1998 Mercedes Benz S420 Repair Question


Topics covered: Engine, Vacuum check valve, Vacuum leak.
Mileage: No information provided.

Asked on July 1, 2010

1998 Mercedes Benz S420 AC Vacuum leak

Air Conditioning problem
1998 Mercedes Benz S420 V8 Two Wheel Drive Automatic 175000 miles

My blower on the climate control stops when I accellerate quickly. Once I reach a constant speed it returns. I am sure I have a vacuum leak and I think it is in the ac control block. I need to know how to get to it. Help. I sent a message yesterday but could not get back in to see if I had a reply. I gave yesterday
Avatar Asked by barnieguest

Answer

Replied on July 12, 2010

Hello, it sounds like the vacuum check valve has failed and needs replacing. This valve is located at inline or at the base of the vacuum source at the engine or firewall. Note: some models feature the valve under the dash on the passenger’s side foot well.

Tiny Answered by 2CarPros Ken
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