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Q: I'm only getting 5.5v to the fuel pump

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I changed fuel pump and filter as soon as I noticed I wasn't getting gas pressure. Then I tested to make sure I was getting power. I only got 5.5v. I tested at the relay and I was getting 11.5. I swapped relays and still not getting power.
My car has 230000 miles.
My car has an automatic transmission.

Hi there. If you are only getting 5.5 volts at the red wire with the black stripe and battery voltage at the relay, then you have a bad connection in the circuit. You should also have battery voltage at fuse 13, which is the fuel pump fuse in the fuse box under the dash. If there is definitely battery voltage at fuse 13 and at the relay, then most of the time the voltage loss is at the relay connection. When the relay is engaged you need to make sure that the red/black wire has battery voltage. If it does then you will need to trace the wire, testing it in increments all of the way to the pump until you find the wire issue. If this is something that you are thinking of having worked on, consider YourMechanic. They will be able to to diagnose your vehicle’s loss of power and perform the repairs necessary to get your car back on the road.

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