2003 F250 Refuses to Start at Random

ford

#1

On Saturday afternoon of Labor Day weekend my dad’s 2003 Ford F250 “died” in the parking lot at my work. It had been running fine all morning, but then I stopped by work, and when I went to leave it barely started, ran for a few seconds at a rough idle (presumably on whatever fuel was already in the system), then died and would not restart. Turned over strongly (new battery a few months ago) but no ignition. Checked the fuses and fuel pump interrupt switch, but everything was fine. Had just put 15 gallons of gas in earlier in the week so I “knew” that wasn’t the problem. Being Labor Day weekend I had to leave it until Tuesday, when I had it towed to my mechanic. He didn’t get a chance to look at it until the weekend, and called me Monday to say that it started just fine for him all weekend, but it could use some gas. I knew I should still have 12-15 gallons in there, so we came to the conclusion that someone had siphoned my gas. Monday night I picked it up, feeling dumb for not checking that more carefully, and drove to the gas station. Sure enough, the gauge registered “E” and the low fuel light was illuminated. Put in 8 gallons. Started the truck and the gauge popped up to 3/4 tank. 8 gallons is NOT 3/4 of a 32 gallon tank. It’s 1/4. The original fuel was still in there! On the way home from the gas station I stopped by work to load up the lumber I had to leave there the first time it died and–you guessed it–died like before. This time the gauge definitely read 3/4 tank with the key on, so the problem was not low fuel. I didn’t want to pay to have it towed again, so my mechanic said he’d come look at it when he got time. I tried to start it a few times throughout the week and on Saturday it started right up and ran strong all the way to his shop, where it continued to start every time we tried it. It could be the crank position sensor, but the confusing part is the low fuel indication. Could the fuel gauge have gotten stuck when the truck was was pulled up on the rollback? And would it have stayed like that all the way to the gas station? I also don’t think it’s the fuel pump because it runs so strongly when it does start. The second time it died the gauge still read 3/4 tank so I don’t think it’s related. Anybody have a similar experience or ideas? The mechanic can’t fix a problem he can’t reproduce, and I really need the truck to pull my 3,000lb landscape trailer on the weekends. My 2000 Wrangler isn’t exactly ideal for the job! Oh yeah, the truck is stock, 5.4L gas, off-road package, tow package, extended cab, long box, auto trans, 85K miles. Thanks!


#2

It sounds like the ignition system may have an intermittent problem. Carry some starter fluid with you so when the trouble happens again you can spray a small amount into the intake to see if the engine will fire up with that. If you get no action with that then you can be pretty assured that the ignition system has failed somehow. It could be due to just a bad power connection to it. Find out where you need to check for power to the ignition and maybe carry a test light with you also to check the power to it.

The fuel gauge problem might be able to be corrected by simply adding some Chevron Techron to the fuel tank. It has helped some others clean the contacts of the level sensor and not have to remove the unit from the tank.


#3

The ground connection for the fuel pump and sender may be deteriorating. You might lift the bed and check the wiring.


#4

If this happens when the engine is shut off when hot, it could be a crank sensor being effected by heat.

One way to check for this is, start the engine and take heat gun and point it the sensor while the engine is idling. If the engine shuts down you know it’s the crank sensor.

Tester


#5

Thanks for the advice. Heat could be causing a crank sensor problem to begin with, but it still won’t start for several days after the initial failure, even though the engine is cold. I guess there’s no way to test a crank sensor that’s “going” bad, only one that’s “gone” bad, right? The faulty connection in the fuel system is a good idea too.


#6

Unless you proven that the ignition system isn’t causing the trouble I would suspect it more than the fuel system as the cause of the trouble.

A faulty crank sensor or bad connection to it will generate a error code.


#7

When intermittent failure to start and an intermittent failing fuel gauge are coincidental the common ground for the fuel pump and gauge sender seems to be a somewhat likely cause. Don’t you suppose?


#8

Will the error code be stored even if the check engine light doesn’t illuminate?


#9

I’m not sure exactly how the fuel gauge reads the level in the tank, but I think the low reading was a fluke caused by the truck being pulled up onto the rollback at such a steep angle. I don’t think the gauge is failing, especially since it read accurately during the second failure to start episode.


#10

Whenever a code is generated it will be stored in the ECU. Some codes are required to be entered multiple times before the CEL light is turned on and the driver is made aware of the issue.


#11

@MattB

I am leaning towards the fuel pump

I have replaced LOTS of fuel pumps on Ford trucks exactly like yours . . . same year and engine

Has anyone had a fuel pressure gauge hooked up to the rail when it wouldn’t start?

Just because the truck runs strong does NOT mean the pump is working correctly

Right now, I am working on a van that has a failing fuel pump

When it starts, the van runs smoothly, and all appears to be normal

HOWEVER, the fuel pressure gauge indicates pressure is considerably too low

And it doesn’t hold pressure after shutting the engine off

I even deadheaded the pump, and it failed miserably

At idle, the long term fuel trims are +10%, not enough to throw a lean code . . . the MIL is not on

Just speaking from experience and throwing some ideas out there . . .