chiett

new fuel filter,new pressure sensor on fuel rail,new module, the one mounted to the frame above spare tire,new fuel pump and according to my edge programer i am still only getting around 3 psi pressure which i am assuming its reading pressure from pressure sensor on fuel rail. it turns over but does not fire. i pulled a coil pack and stuck a plug in it and turned it over and its getting fire to plug. before it completely quit running i started noticing that when i went to push on gas pedal that my fuel pressure reading would drop to like 2 psi and than spike to like 58, it only seemed to do that when i was barely pushing on the peddle, as long as i was able to hold a fare amount foot on the peddle it ran fine. any ides .

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techrep

iTrader: (1)

What motor you working on Chiett ??

chiett

5.4 triton flex fuel

chiett

does a bad throttle position sensor sound like the problem, I know there should be a way to test that with a volt meter. if it is some how stuck in WOT, I believe that would cause a no start right?

techrep

iTrader: (1)

never heard of it getting stuck at WOT...you can pull the throttle body and clean it ...and check the TPS.

chiett

I looked down in the throttle body and it looks good but I have not taken it off to check it..

chiett

not acutely stuck but sending a wot signal.

Mod (Ret.)

The variable switch on the side can be tested; if you have access to a tuner or code reader, they can read and show the TPS readings as you press the drive by wire pedal (some still call it the gas pedal).

A digital multimeter can also be used at the TPS's connector, but I do not know the pins you would need to put the meters two probes on.