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Q: No fuel pressure at the rail. Changed the pump, filter and pressure regulator. Could this be electronic or the cpi unit?

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Drove to the store, no issues. In and out in less than 5 min, it would not start. Had it towed home. Tried there and it fired up. Drove it to work and back, no issues. Following day, no start. Changed the fuel pump, filter and regulator, still will not start. Checked pressure at the rail, only getting 20 lbs then dropping to 18 and holding. Could this be electrical or the cpi unit?

My car has 278 miles.
My car has an automatic transmission.

A: Hi! I’d suggest performing a voltage drop t...

Hi! I’d suggest performing a voltage drop test at the fuel pump connector. That will verify that you have good power and ground at the pump. You could also put a new fuel pump relay in it, or swap it out with one of the others to see if it makes a difference. You should have at least 60 psi while cranking. If you block the return while cranking and pressure goes up, it’s a bad regulator. If not, and power and ground to the pump are good, its a bad pump. If you need assistance in this process, a certified mobile mechanic from YourMechanic can come to your home or office to inspect the issue and provide any necessary repairs.

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