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Q: fuel pressure fluxtuates while runninh

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I attached my fuel pressure gauge it reads at 60 but shaky when i hit the throtle it straightens out it droped down to 40 a couple times is it my fuel regulator or fuel pump

My car has 140000 miles.

A: Hello. Your vehicle uses a new design that ...

Hello. Your vehicle uses a new design that integrates the pressure regulator into the fuel sender assembly. This eliminates the return plumbing and external regulator, keeping hot liquid fuel out of the tank which reduces the potential for evaporative emissions. Your pressure reading should be 50 PSI minimum. If the pressure drop to 40 PSI is extremely brief, it might be acceptable. If you have never changed the fuel filter, putting a new filter in could mitigate the dip you are seeing. At 140,000 miles if the filter hasn't been changed you should change it anyway. A restricted or plugged strainer can also cause pressure dips and so can poor connections at harness connectors and a poor ground circuit for the fuel pump. If you were led to the fuel system while trying to diagnose an engine management issue and you still need technical assistance with that issue by all means contact YourMechanic for further help.

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