I have a 2001 F-150 with a 5.4 EFI and an A/T. About a week ago while driving, the engine just died with no warning. There was no sputtering or chugging, just went dead. I placed the trans into Neutral and the engine started right up. But a few miles down the road the same thing happened again.
Following some friends' suggestions I changed the Crank sensor but the problem keeps resurfacing. Since I replaced the sensor the truck ran fine fro a few days. Then as I was exiting an interstate and slowing down on the exit ramp for a yield sign. As the vehicle speed decreased I felt the tranny downshift and then it completely went dead. I pulled over to the shoulder, placed it in Neutral and it started right up. I then drove it five miles to my destination and then a few hours later I drove it 25 miles home with no problems.
The truck's not throwing any codes and it happens when cold as well as when hot. I don't think it's gas related as usually when the fuel delivery is interrupted or cut off, engines usually sputter before dying; mine just shuts right down.
I spoke with a service writer at a Ford Dealership and he could not offer any definitive solutions. He said that it could be anything from a loose wire, bad ground, or water intrusion into one of the electrical circuits.
Nonetheless, yesterday I drove to a store and after five minutes in the store, the truck would not start at all. I have had problems in the past with the EEC relay (located under the hood next to the power distribution box). There have been times when the truck wouldn't start and I would tap on the EEC relay and push the wires into the connector and the truck would start right up. I previously changed the relay and I reinforced the wire connections. Well, I still had the old relay in my glove box so I tried it and the truck started right up. I bought a new relay but had not yet installed and today the same thing happened so I installed the new relay and it started.
Then while driving home today, three times the engine cut off on me but each time started right up.
When I got home it died once in my driveway and then started . While it was running I began to poke around under the hood, tapping and jiggling various connections and when I tapped on the power distribution box the engine died and would not start again.
I removed the power box and check all of the connections between the EEC relay and the box and all were okay. I also checked all fuses inside and under the hood and all were okay. I did notice some grease or lubrication on the terminal connectors of the EEC relay harness plug. I sprayed them with an electronic cleaner and reinstalled the relay and the truck started right up.
Now I'm thinking the problem may have been poor contacts at the EEC relay connection. I'll know more tomorrow as I have to take a 25 mile drive.
Any suggestions or help would be greatly appreciated.

Tony

 

I just finished reading about this and now I can't find it give you the link. I think the guy had to fix the wiring where it comes into/out of the power distribution box. I wish I could remember more, but know that you are probably on the right track. It has something to do with the connections to the pdb.

If I find the other post, I'll come back here and link it.

Hope this is okay as I was reading on another forum. Here is the link. It sounds an aweful lot like what you've got going on.

http://www.ford-trucks.com/forums/90...-box-help.html

 

Also check the fuel pump control module and DPFE

 

Although the fix was not definitive, the problem has apparently been resolved. My belief is that the EEC relay blades were making poor contact in the relay harness plug. As I had said, there was a greasy type lubricant in the harness plug where the blades insert. Apparently by cleaning them with an electrical terminal cleaner spray, the EEC relay is now making good contact. I did notice that prior to cleaning the terminals, the relay could very easily be pulled in and out of the harness plug. Now, that the terminals are dry, the relay appears to be much much snugger in the harness plug.
I have already clocked over a couple of hundred miles with numerous starts and stops and the engine has always started immediately and it has no longer died while driving.