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Q: Black smoke and rich fuel the codes P0191 & P0452 and short trim bank 1 & 2. Both at -28.9

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My car Ford Explorer with a strong jerk and thick black smoke and the engine stops suddenly and WHEN i test it by obd2 there is cods p0191 & p0452 i replace fuel rial pressure sensor and nothing change, the mechanical man side PCM needs to be changed Did his talk is true because the PCM does not give 5V to sensors i forget when i do freeze frame i notice both short trim bank 1&2 = -28.9 and long trim bank 1& 2 = 0
i need your support ples

My car has 76875 miles.
My car has an automatic transmission.

A: Hello. You have 2 separate problems here. T...

Hello. You have 2 separate problems here. The P0191 (fuel rail pressure sensor circuit problem) may just be a symptom - it is reporting suspect fuel pressure on the rail. The fuel pressure on the rail is controlled by the fuel supply system (pump & filter) and the fuel pressure regulator. Check fuel pressure on the rail with a gauge, and the engine running, to determine what the actual pressure may be. Then you can pursue diagnosis of a fuel supply problem or a fuel pressure sensing problem.

The P0452 code indicates a pressure sensing problem with the EVAP system purge line pressure (tank and purge line). This is part of the fuel tank pressure test done after each engine "start" cycle. To have this all addressed I recommend having a certified technician, like one from YourMechanic, inspect your vehicle in detail to give you a second opinion.

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