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Q: Fuel pump will not kick on.

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OK So I have replaced the fuel pump, fuel pump relay, and the fuel pump fuse. Installed everything and the fuel pump will not kick on. So I dropped the tank again. First through the pump wiring harness, I check the voltage. At the Purple wire and the black/white wire I got 10v (level gauge). Then I checked the gray wire and black wire while someone turned the key to run, I got 12.98v for about 5 seconds and then had them crank the engine and got anywhere from 10-12.5v while cranking. So I then thought it might be a faulty pump, Autozone gave me a new pump to try and still same issue. So i then thought it could be a ground. I checked the ground and it came out to be .3 ohms, which i believe is ok. Then i check the continuity of all the wires on the pump harness and they were fine. I read something online about the passlock system, although the security litght was not flashing i tried the 10 and 30 min relearn still nothing. BTW checked every fuse and relay. No engine codes w/ obdII

My car has 238000 miles.
My car has an automatic transmission.

A: With fuel issues such as these, there are a...

With fuel issues such as these, there are a few things to consider first. If the fuel pump and all of that has already been replaced, then it is likely the issue is not with the fuel pump itself. The fuel system is controlled by the cars ECU and relies on the input from various sensors such as the oil sending unit and engine coolant temperature.

If any fault is found in the system, the ECU may not allow the fuel pump to run. The low voltage when cranking is a little strange, the most common cause of that would be that the battery is weak. If the battery is weak it may show 12 volts but will not have enough power to run any of the systems. A qualified technician will have little trouble diagnosing this battery fault firsthand and perform any repairs required to get your pump working again.

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