. I once had an associate back in my Navy days who could not start his van, we took most of his ignition system apart and could find no open wires or blown fuses that could account for his van not turning over, we sort of gave up looking and put everything back together, somehow once we put all the wires back, the van started up! Found Fuel Pump Control Module on frame was corroded and cracked. If you do and you are going 75 80 on the highway coming to a hill will cause it to race that high. I'm a shade tree mechanic but these simple things work sometimes. Applied direct power to fuel pump and it will run. Now truck won't start again. Carefully clean throttle body with proper cleaner.
. Then when the hill is crested it will slow down, I don't like it either but it is the nature of the beast. I often cancel the cruise on big hills on the highway so it doesn't do that. I suggest check the easy things first. Diagnostic Aids: Check the harness and connection.
Something I was taught in the Navy a long time ago, check the simplest items first, like the wires that connect the fuel pump or control module, we were always told to check the fuses first, then check for anything in the wiring or circuitry that could mimic a blown fuse or open wire or an increase in resistance which would drop the voltage necessary for normal operation significantly. . You have a module controlled, variable pressure fuel pump circuit. I'm still trying to isolate why my 2003 F-150 4. Do you have any suggestions to help figure out why 2005 F150 with 4. You didn't mention if you have the cvt trans. A corroded wire seems like an obvious source for this problem, if you can isolate the wires that supply power to the fuel pump or the control module, I'd check to see if corroded wires are open or have enough resistance due to the corrosion that the corrosion itself is dropping most of the voltage or the current required to operate the fuel pump or the control module itself.
Had this problem approx 1 yr ago. I've been tld that you can put a recommended cleaner into your fuel tank and this can sometimes cure the problem - worth a go. Fuel pump still will not run. From what you listed, it sounds like the simplest answer is that following the corroded control module trail, it seems likely that I'd try to find out at what point does the battery voltage get cut off from reaching the fuel pump terminals? For Crown Victoria, Expedition, Explorer, F-150 4. Can apply power to pump and it will run. Checked all fuses and relay.
Vacuum lines, could cause a lean condition, fuel filter restricting the fuel flow lean condition. . . . . . .
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