Q: Low fuel pressure at the fuel rail (30psi) then drops to 10psi occasionally while idling. The fuel sending unit was just replaced. 2004 Dodge Dakota

asked by on January 31, 2017

Just replaced the fuel sending unit, but still have low fuel pressure (30psi) and flictuations (down to 10psi). The truck runs decently, but has low power and bad mpg. It also has trouble starting when trying 15min to 2hrs after turning it off. I've already replaced 02 sensors, cam pos sensor, crank pos sensor, throttle pos sensor and map sensor. Any ideas? I'm out of guesses. Thank you Dennis

My car has 160000 miles.
My car has an automatic transmission.

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Hi there - yes, you clearly have a fuel supply issue, mainly focused on getting enough pressure in the fuel rail to the injectors. Check problem codes first, even if the Check Engine light is not illuminated. I suspect your problem is related to either the fuel pressure regulator, or the fuel pump check valve. either of these could cause low fuel pressure. A clogged fuel filter or weak fuel pump could also be the source here. I recommend a loss of power inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

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