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I bought my 04 f150 from my aunt when my uncle passed. It unfortunately has the 4.6L triton in it. My uncle was the only owner and the only thing he ever changed/ had changed was the window motors, oil, and just before passing the tires. Due to poor life choices this is my first and only vehicle purchase. I am not mechanically inclined and what little I know has come from this site, YouTube, and what little my uncle taught me cause my dad is a POS. I started having issues where my reverse worked when it wanted to. I sometimes had to shift in and out of gear to get it to catch and I was dreading the transmission when it suddenly started working fine but I lost acceleration power. It would still reach speeds of 90+mph ( testing of course...) but it would take me 15-20 seconds to reach just 45mph. Ontop of that I would have power surges where with my foot off the gas pedal and even while braking the truck would continue to try to accelerate on its own. I started looking for answers then but this being my only means of transportation I had to continue to use it for work. One day I stopped at a stop sign and my engine stalled. I tried cranking it and it started but when I put it in drive and pressed the gas it stalled again. It did that 3 times then refused to turn over and just made a sort of thunk sound when turning the key. Once it was towed home I started looking for answers. Due to unforseen circumstances I lost my job and my no longer running truck is now also my home. I am still, 6months later, looking for answers to no avail. I have pulled the starter and alternator, had them tested at advance auto and they are good so I reinstalled them. I have been debunking suggested part after suggested part and I am at my whits end. I finally found a damaged fuel pump drive module and bought a replacement. I was told afterwords that I would have to take it to a mechanic and have them code it for my truck or it wouldn't work. So, first of all would this part if damaged or malfunctioning cause my issues or should I keep looking. Second is it true that I need to have the part coded for my truck for it to work or will simply installing it allow it to work, even In limp mode if need be. And third if the part does need coded do I need to get my truck to the mechanics or can I simply take the part there. I am in desperate need of help as my truck/home may soon be towed and I will be on the streets I'm gonna try and post a pic of the damaged fuel pump drive module if I can figure out how
Ok so starter, alternator, all fuses and relays are good. Replaced FPDM and still no crank. When battery is connected everything is powered but when I turn the key I just get a thunk. When coded I get a code for a speed sensor, and O2 sensors would these cause a no crank? Or should I move straight to the fuel pump?
No. It needs to crank first. Then worry about fuel.
pulled the starter and alternator, had them tested at advance auto and they are good so I reinstalled them.
When battery is connected everything is powered but when I turn the key I just get a thunk.
What about the battery. Did Advance test it too? Result?
Have you tried jumping the battery, or fully charged it before trying to crank? Results?
Battery can be strong enough to power dash lights but not strong enough to turn starter.
[QUOTE]lost acceleration power... would still reach speeds of 90+mph... would take me 15-20 seconds to reach 45mph... stopped at a stop sign and engine stalled... started but when put it in drive and pressed the gas it stalled again...
did that 3 times then refused to turn over and just made a sort of thunk sound when turning the key...
Replaced FPDM
[/QUOTE]
All of these symptoms could be caused by a faulty FPDM or fuel pump, or other problems.
Before addressing them though, the engine needs to crank.
The "thunk" could be due to a weak battery.
would have power surges where with my foot off the gas pedal and even while braking the truck would continue to try to accelerate on its own.
Don't have any idea why it would accelerate on its own.
Do you have or can you get an OBD code reader? Advance can check for codes if it starts. Knowing what codes it has, if any, can be helpful.
[QUOTE=getterdun;5282494]No. It needs to crank first. Then worry about fuel.
What about the battery. Did Advance test it too? Result?
Have you tried jumping the battery, or fully charged it before trying to crank? Results?
Battery can be strong enough to power dash lights but not strong enough to turn starter.
lost acceleration power... would still reach speeds of 90+mph... would take me 15-20 seconds to reach 45mph... stopped at a stop sign and engine stalled... started but when put it in drive and pressed the gas it stalled again...
did that 3 times then refused to turn over and just made a sort of thunk sound when turning the key...
Replaced FPDM
[/QUOTE]
All of these symptoms could be caused by a faulty FPDM or fuel pump, or other problems.
Before addressing them though, the engine needs to crank.
The "thunk" could be due to a weak battery.
Don't have any idea why it would accelerate on its own.
Do you have or can you get an OBD code reader? Advance can check for codes if it starts. Knowing what codes it has, if any, can be helpful.
So i had my battery charged at the lawnmower mechanic next to my work. The guy charged it and tested it and said it was good. I put it back in my truck but did not reconnect the cables so nothing would drain it. But a week later my battery was dead. My sisters fiance works at NAPA and he tested my battery and said it had a bad cell and won't hold a charge. 2 yr warranty went out January 21st... so next step is a new battery and go from there
