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Q: Engine slows, shakes, clicks, and quits - 1993 Mercedes Benz 500 SEL

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After having driven a few miles my car slows down, stops, I press on the gas pedal to accelerate, the car starts to shake and then a clicking sound and the engine dies. The battery light comes on and the car will not start for 30-60 minutes. Then it runs fine. I have researched and from what I understand, the problem might be the fuel pump relay. I have been searching for the fuel pump relay seat. I have replaced 8 spark plugs, fuel filter and connector line, air filter, fuel vent valve, charcoal canister, but none of this solved the problem. The engine still quits. An interesting note is that on a hot day when I’m driving on the highway, it does not stall. What is your advice for what I should do to solve my car’s problem?

A: Hi there, thanks for writing in. The fuel p...

Hi there, thanks for writing in. The fuel pump relay is located in the trunk on the right side below and to the right of the computer module. I recommend replacing the relay first after checking connections for any corrosion on connections. If the relay shows signs of heat damage then the fuel pumps may be drawing excessive amperage and would need to be replaced along with relay and its connection.

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