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Q: No fuel to pumps - 1991 Mercedes-Benz 420SEL

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I’m not getting any power to the fuel pumps. They don’t seem to be pumping. I checked the multi meter and there is no power going to them. Do you know what’s wrong? How can I fix this?

A: Since you know how to use the multimeter, y...

Since you know how to use the multimeter, you are 2 steps ahead already! Start with power to the fuses (fuel pump), then the fuel pump relay to follow the power path. It’s also possible that the ignition switch, and any other safety interlocks like the oil pressure sensor (no oil pressure, no fuel pump power) that may be involved. A professional mechanic, like a certified technician from YourMechanic, can help diagnose and make necessary repairs to your fuel pump system and oil pressure sensor.

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