Cant figure it out 2005 5.4L 175k
07-23-2015, 10:39 AM
#1
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Cant figure it out 2005 5.4L 175k
Bought the truck in 08/12. Love this truck. To make this short I have replaced; Fuel Pump, FPDM, Plugs and COP's, Fuel rail Pressure Sensor, followed the power wire from the FDPM and found it corroded bad so I replaced it, also changed the ground location on the FDPM, I have checked all the wires from the FDPM to the drivers seat, checked all fuses.
Before I replaced the plugs and COP's it would take awhile to start and had no power, I couldn't even pass someone. After replacing she would start right up and I had a lot more power back but still when I would pass someone I could feel it jerking, not bad but noticeable, just not smooth like it should be.
So the other day I go to start it and let go of the key before she actually fired, heard a air sound from the engine like air brakes letting go. then she took forever to start. Now she takes about 10-15 sec to start and will run rough for the first 10-20 seconds of starting then runs fine. I get down the road 200 ft and she sputters for 10-15 sec then runs fine. I have noticed when the fuel tank is under 1/4 and I take off quick of turn quick she cuts out for 2-3 secs then comes back. Check engine light keeps coming on saying Fuel Rail Pressure Sensor but I have already replaced that. Besides that she runs fine with the exception of the sputter when I pass someone.
I am led to believe that a wire is shorting out somewhere or my PCM is bad.
I'm just reaching out here any help is appreciated.
Before I replaced the plugs and COP's it would take awhile to start and had no power, I couldn't even pass someone. After replacing she would start right up and I had a lot more power back but still when I would pass someone I could feel it jerking, not bad but noticeable, just not smooth like it should be.
So the other day I go to start it and let go of the key before she actually fired, heard a air sound from the engine like air brakes letting go. then she took forever to start. Now she takes about 10-15 sec to start and will run rough for the first 10-20 seconds of starting then runs fine. I get down the road 200 ft and she sputters for 10-15 sec then runs fine. I have noticed when the fuel tank is under 1/4 and I take off quick of turn quick she cuts out for 2-3 secs then comes back. Check engine light keeps coming on saying Fuel Rail Pressure Sensor but I have already replaced that. Besides that she runs fine with the exception of the sputter when I pass someone.
I am led to believe that a wire is shorting out somewhere or my PCM is bad.
I'm just reaching out here any help is appreciated.
07-24-2015, 07:37 AM
#3
Put a scanner on it and watch the fuel pressure. It should still be pressurized and maintain pressure when you shut the truck off. If it doesn't, you have a leak (which you should already smell anyway). The scanner will also be able to monitor your vacuum / boost when the engine is running, so watch those numbers at idle and when you open the throttle to see if there's a leak there as well.
07-24-2015, 07:56 AM
#4
Mark
iTrader: (1)
Clogged cats ?