I am new here and I have read some of the other posts to find some help, but none of them seem to match.
I have a 2008 F150 with a 4.6 litre in it. Last year I dropped a couple of plugs and had a factory new, second generation 4.6 installed. The motor only has about 25,000 on it while the rest of the truck has about 160,000.
I was driving back roads in western Mass and went over a small, about four inches deep, pothole. I was driving about 35 miles per hour.
I didn't get any associated master warning lights. The RPM started rolling back from about 1700 to 0, and when they got to 0, the engine shut off.
There was no previous sign of a fuel pump going bad, or of a bad fuel filter, which is also less than a year old.
The truck has plenty of electrical power and turns over strong but wont start.
I checked the #9 fuse as identified in the manual but couldn't find an actual relay for the fuel pump, so I'm assuming it just has the 20 amp fuse which was good by the way.
I'm thinking that the fuel pump would have given a few warning signs prior to ****ting the bed, but maybe not.
I did check the emergency fuel shutoff switch to make sure that it had not activated when I hit the pot hole and unless I'm resetting it incorrectly, it doesn't seem to have been set off.
Any ideas would be greatly appreciated. Thanks in advance.

 

The fuel pump switch pushes down to reset. Its designed to trip from an excessive horizontal force, I don't think a vertical jab would trip it. If it IS tripped, the head of the red button will be sticking up above the shroud and be plainly visible. I would look at the air filter to see if its wet. A sufficient blast of water in the wheelwell might have got into the intake. I'm thinking more likely the driver module (FPDM) got a shot of water in it. You have to drop the spare tire to get to it. Unbolt it from the frame and see how it looks. If the aluminum case is obviously corroded, you probably have your culprit. A sudden death of the fuel pump is probably my last suspect, as with you. Good luck.

 

I just dropped the spare tire to pull the driver module off. It doesn't look that bad, but we get a lot of salt on our roads so..............
I guess it is cheaper to throw a module at it than to throw a fuel pump in it. I'l let you know how it goes.
Cheers !

 

So I replaced the fuel pump driver module and no joy. The truck cranks over strong but doesn't start still. There are two codes that the truck took; P0106 and P0191. The P0106 seems to be a PCM code and the P0191 seems to be a fuel rail pressure code.
Anyone see a logical next step? I'm thinking the rail pressure sensor. In my first post I didn't allude to the fact that when I put my head down close to the tank and turn the key, I can hear the fuel pump run for a few seconds, So I'm thinking it works.

Sincerely,

Bill (the 32 year F-14, F-15, and A-10 Crew Chief that can't seem to troubleshoot his truck)

 

Both are circuit codes.
You have a harness or grounding issue that vibration brought from the jolt.
106 is MAP/BARO pressure sensor circuit,.
191 is fuel rail sensor circuit. This controls the pump pressure because it is a single pipe system.
Look at the area they both are physically common to.
Good luck.

 

If its orig I would change it . bump could have broke some stuff loose .
I believe your fuel pressure isn't coming up on the rail . Unfortunately they removed the test valve on fuel rail . I guess you could try to inject some fuel into the throttle body to see if is lack of fuel . I haven't tried that, some have tried starting fluid .
I also had trouble with the fuel module connector . I put a new module in it and it kept shutting down and I went back and forth between the old and new . Turned out to be a rolled gasket in connector , I pulled it out a year ago and no more trouble .

 

Could you pull off fuel filter side towards engine, put a rubber line on it to see if it will pump into bucket ?

 

The connector for the fuel pump is under the plastic cover on the outside driver's side frame. That area tends to build up with crud and those connections are prone to corrosion. I would check there...