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CEL came on two days ago and read out a P0190 - Fuel rail pressure sensor A circuit.

I checked the connectors that run from (or anywhere close to) the fuel rail and they all seem ok connection wise. The car isnt running funny at all and as far as i can tell performance hasnt taken a hit. I cant tell where all the wires run from the fuel rail, and i havent had a chance to really look at it.

Got any tips on what to look at or how to fix the problem? Hoefully its not the rail itself.
 

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P0190 - Fuel Rail Pressure Sensor Circuit Malfunction (FRP) The comprehensive component monitor (CCM) monitors the FRP sensor to the PCM for VREF voltage. The test fails when the VREF voltage from the PCM drops to a voltage less than a minimum calibrated value.
VREF open in harness.
VREF open in sensor.
VREF open in PCM.
Verify VREF voltage between 4.0 and 6.0V.

I'm going to throw another one in there- loose ground. Look around your engine for a copper shoelace that connects the back of the cylinder head to the firewall. At least I think that's where it is on the SVT. Somewhere there should be a ground that goes from the cylinder head to the firewall. Sometimes loss of that ground can affect V readings to some parts. You should also double check the security of the ground wire that connects the neg battery terminal to the chassis, and the ground wire that connects the neg terminal to the engine block.

Chances are like 10% that will fix it, but you'd hate to purchase a new fuel sensor for $150 to face the same problem in a short time due to bad or incomplete grounding. After that, you can be fairly certain that the sensor is your fault. You can take some time to trace down the wiring that goes back to the PCM, but if there's no immediate damage to the wiring harness under the hood, then I'd say you're not going to find any damage inside the car- unless you've been in there recently yanking on wires.
 
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