2000 f250 V10 I have searched this problem and seen many threads but I can not seem to find one that has a solution I am looking for. This is probably my real problem.
Problem: More often than not when the key is turned to run (?), prior to engaging the starter, the fuel pump does not turn on for its 5 seconds. I have installed a fuel pressure tester gauge to watch the fuel line pressure. It was a little shaky to diagnose because if the line had pressure/fuel from the previous run it will start and run a short time and then die from lack of fuel. Unless the fuel pump activates when the key is turned to run, prior to full start, then there will be no fuel coming from the pump. No start. If you work the key to run a few times until the pump engages its good to go. The truck has never died while driving, once it gets that initial pump activation it runs good until the next start up cycle. When the pump does work it builds up to good "book" pressure and holds it at 39 when the engine is shut off.
We have put off changing the fuel pump for obvious reasons but can not see how it could be the problem since it has never quit once after we get it started. Are we wrong?
We know the fuel shut off is on as it will run.
We have changed the key lock tumblers, the ignition switch and the fuel pump relay. (behind the radio).
Next up is to re-seat all the fuses and relays in the main fuse panel box under the hood. I just read that today on FTE. Thanks.
Is there a test we can do or some engine codes we need to look for?
This problem is getting old fast.
Any ideas or links I may have missed would be be greatly appreciated.
I am very interested in hearing what other have done to fix this.
Thanks for your time. Roy.

 

The only way to test the circuit properly is to disconnect the power connector at the pump, and test there for power and ground. If you have good power and a good ground, then the pump is bad. However, to do that I am almost sure that you would have to drop the tank---I don't think you could unplug the harness while the tank is in the installed position. From your description of the problem, it sounds like the pump is binding and won't start to spin after a prolonged (overnight) rest.


You can test for a stuck (binding) pump by having someone under the truck with a rubber hammer. Try to start the engine, and if it just cranks but won't fire, have them bang the bottom of the tank with the hammer while you are cranking it---if it all of a sudden fires up, you know the pump was stuck and the banging freed it up---It's crude, but it just might make you more confident that it is really the pump, and not an electrical problem.






RON

 

Possibly. Need more data.

Yes. Connect a test light to the output of the inertia switch (do not disconnect the FP). Watch that lamp for the TWO SECOND initial priming cycle. If that light comes on during that period, then you KNOW that everything forward is working (PCM, relays, fuses, etc) and you have only the pump, its wiring from the inertia switch rearward, and the pump circuit's ground left as possibilities. Cuts down on the diagnostics that way.

Note that you only have power applied to the pump for TWO SECONDS until the PCM detects that the engine is firing (looks for accelerating crank signal). Therefore, if you're continually cranking the engine without first turning the ignition back OFF then ON again, the pump will not start back up until the next cycle, assuming the thumping did the desired job.

 

I had the same problem with my 2000 f250 5.4L. After a lot of testing circuits it turned out to be a dirty ground attachment at the firewall.

 

The results of the test light at the inertia switch will rule that either in or out as a possibility. If the test light fails, it's possible (one of many remaining). If the test light passes, it isn't and the only possibilities are the ones I gave above.

 

Hey 9rudy9 - there is a good possibility cleaning the ground connection didn't solve my problem (truck is currently starting however.) If you find a solution to your problem would appreciate hearing about it. Thanks

 

Great ideas everyone thanks. I am going to try that inertia switch test on my oldest boys f250, now that the youngest has his f150 out of my garage. That was a water pump issue that due to the frozen bolts required sawing off the timing chain cover. What a mess that was. Sometime after fixing the snowblower and in between the new starter in the daughters Buick. Merry Christmas and thanks again.

 

Well due to life getting in the way we didn't do the inertia switch test we just changed the fuel pump. This seems to have fixed the problem. He has 106K on it. I wouldn't hesitate to guess that's at least 11,000 gallons of gas. We got 14mpg once or twice on trips no trailer. Town 10 or less. 12-13mpg was normal hwy.
The last few years this thing has been crawling around in the woods. That gets 9-.
We dropped the tank, not the bed off method. The filler tubes are always a pain. We ended up cutting them and replacing. We lowered the empty tank as much as possible with a jack prior to unhooking the lines and power. Not sure how this could be done as the book said with the bed on. We dropped the spare tire to gain access to the rear of the tank to attach the rear vent and help re connect the filler hoses. This should go much faster in 2030.
This is a 2000 F250 extended cab short box v10 4x4.
Thanks for the help. Roy.