Ford f150 4.6
OK , according to the info you provided, we have spark coming to the plugs and some fuel is getting to the injectors which from our tests indicate the fuel should be getting into the cyls, but is not because the plugs show no indication of being over fueled.
What is needed now is a scan tool that can tell us the desired and actual fuel pressure . Without that we are at a stumbling block not knowing if we are getting good fuel pressure.
What is needed now is a scan tool that can tell us the desired and actual fuel pressure . Without that we are at a stumbling block not knowing if we are getting good fuel pressure.
Just seeing fuel come out of a line is not sufficient to determine the pressure available.
The scan tool or gauge is required to provide that answer.
Going back a little,
you state you replaced the fuel module, was that the fuel pump in tank module or the fuel pump driver module?
They are 2 separate items. The FPDM , fuel pump driver module, controls the fuel pump according to the pressure signal sent to the PCM by the fuel pressure sensor.
The PCM sends a modulated signal to the FPDM which will control fuel pressure from the pump to the pressure sensor and to the injectors.
If,,,,,,,,,,,,,,,,,,you didn't check out the FPDM , you should look at it . It should be located just over the spare tire and is known for developing corrosion problems between the chassis mounting and the module itself.
Also known for poor ground problems there too. You can see where the ground wire is fastened to the chassis.
The scan tool or gauge is required to provide that answer.
Going back a little,
you state you replaced the fuel module, was that the fuel pump in tank module or the fuel pump driver module?
They are 2 separate items. The FPDM , fuel pump driver module, controls the fuel pump according to the pressure signal sent to the PCM by the fuel pressure sensor.
The PCM sends a modulated signal to the FPDM which will control fuel pressure from the pump to the pressure sensor and to the injectors.
If,,,,,,,,,,,,,,,,,,you didn't check out the FPDM , you should look at it . It should be located just over the spare tire and is known for developing corrosion problems between the chassis mounting and the module itself.
Also known for poor ground problems there too. You can see where the ground wire is fastened to the chassis.
Last edited by hanky; Mar 14, 2021 at 06:01 AM.
What was the pressure the scan tool found?
Also, if there was a short to ground at the FPDM because of the corrosion it might have caused a fuse to open..
We need to know if the 5 volt reference voltage is available to all the components on the circuit. Can you check and verify that?
Also, if there was a short to ground at the FPDM because of the corrosion it might have caused a fuse to open..
We need to know if the 5 volt reference voltage is available to all the components on the circuit. Can you check and verify that?
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