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Q: P0191 code coming on - I already changed the fuel pump, fuel pressure sensor, and driver fuel module

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Have code p0191 changed fuel pump driver fuel module and fps what other this guy could it be and does my truck have a fuel regulator

My car has 150000 miles.
My car has an automatic transmission.

A: Hi there. Check the fuel pressure on the ra...

Hi there. Check the fuel pressure on the rail with the engine off and the key on, with the engine running at idle, and the engine running at 2000 rpm. If the fuel pressure is greater than 35 psi, then the fuel pressure sensor has failed. If the fuel pressure is lower than 35 psi, then the fuel pressure regulator has failed or there is a plugged fuel filter. If you need further assistance troubleshooting your vehicle, then I recommend having a certified professional, like one from YourMechanic, diagnose the Check Engine code in person to ensure that the correct repair is made.

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