Engine shut off on highway. Replaced fuel pump

LOTSABYTES

MEMBER
2019 FORD F-150
5.4L
V8
4WD
AUTOMATIC
306,000 MILES

Engine shut off on highway. Replaced fuel pump, sending unit fuel level, instrument panel assembly, fuel pump relay, inertia switch, but all old and new parts tested good on ohmmeter. Fuel pump relay 301 is operating and old/new fuel pumps run with direct battery power. Both positions on inertia switch between common and normally open and normally closed working with the meter. 12vdc also coming into the switch with ignition on. Traced wiring harness from fuel pump assembly at fuel tank on frame up to the cab. Dash panel doesn't cycle gauges, only lights for ABS and Theft for alarm, pump doesn't cycle and relay clicks okay. Also connected a spare PCM computer, but so far no changes in operation. No error codes on either PCM.

2 Replies

JACOBANDNICKOLAS

MECHANIC
109,740 POSTS

It sounds like the crankshaft angle sensor, main control relay or fuel pump is going out. To be sure lets go over these guides to help us fix it the problem. The should scan for codes as well you could have a MAF or MAP sensor going bad which will leave a code (a bad crankshaft sensor will not leave a trouble code FYI). When the engine stalls lift he hood and check to see if any of the relays are hot in the main fuse panel (PDC).

https://www.2carpros.com/articles/engine-stalls

and

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please run down these guides and report back.

You mentioned the theft light. Does it go off or stay on? Also, I realize you scanned the computer. However, did you scan the can bus? CAN stands for controller area network. If you scan the can bus, it will identify codes in any of the modules which may be helpful.

Here is a video showing how to scan the can-bus system:

https://youtu.be/InIlnsjOVFA

Let me know if that has been done.

Take care,

Joe