Strange Fuel Pump Relay Issue - Mercedes-Benz Forum

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post #1 of 1 (permalink) Old 09-20-2010, 03:27 PM Thread Starter
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Date registered: Sep 2010
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Strange Fuel Pump Relay Issue

1988 420SEL. It's been a wonderful car except for one annoying problem. Intermittently the engine starts & dies, starts & dies. I pull the fuel pump relay out and replace it with a spare I have and it fires right up. It may be fine for a week or two and does it again. Go through the same routine and it fires up and drives fine. Sometimes I can just pull it out and pop it back in and it runs fine.

Is this a case of two intermittent relays by coincidence or something else going on. Pins in socket look fine. Someone said there may be a solder joint inside the relay module that was a known defect (?) I'm fairly competent at elctronics & wiring so not afraid to take it apart if it's something I can fix. Or should I just chalk it up to two bad FP relays?
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