When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I have an 89 F350 with a 7.3. After about thirty minutes of driving I noticed the engine gained RPM's then stalled out. It would crank back up after two or three tries and I could drive about a 1/2 mile and it would do this again. It happened four times before I made it home. I checked the manual fuel filter and have plenty of fuel. I then replaced the filter thicking it was dirty. Still does the same thing. Could it be the fuel injector pump?
Welcome bigd62! How long had you been driving before that happened? Sounds like
air in the system or you were running out of fuel. Hopefully you don't have sediment
in your fuel tank or a dirty screen on the sending unit.
Fuel pump should pull at least 12 inches hg on the intake side, if not it should be replaced. You can check to see if you have decent pressure by removing the
cap on the Schrader valve on the fuel filter head. Looks like a valve stem cap
for a tire rim. It should shoot across the motor. Hope that helps
Last edited by diesel_988; Jan 7, 2005 at 02:44 PM.
Thanks deisel 988. I drove the truck to work in the mourning and this happened coming home. I lean toward losing fuel also. I'll have to check it out. Thanks again
If either of your tanks is well above 1/4 full switch to it. The tank pickup tubes will break off at the 1/4 tank point and you will suck air. This will happen on both FR and RR tanks.
Do pressure and flow test on the fuel at the Schrader valve on the filter(FSS- fuel shutoff switch disconnected). Remove the tire valve core and hook a hose and pressure guage on it should see 4-6 psi when cranking. Then do a fuel quantity test same place, should see 1/3 pint in 10 seconds of engine cranking, route fuel to a suitable container with a hose.
I have good pressure at the schrader valve as we ran a gauge while running. I also fixed a small leak in the supply line and checked for leaks on the return lines. The return lines are new as I put a kit on about a year ago. I was wondering if my fuel tank switchover valve could go bad and let fuel come from both tanks. I noticed that the rear tank is way below 1/4 and thats futher than I ever run that tank. Could it have done this and is sucking air from the rear tank.
More likely the valve didn't switch at all and you are still running on the back tank. With the engine off and the key in the run position you can hear the switch click when you switch tanks but that does NOT mean that it did actually switch. It does mean that the solenoid is working but it may not be moving the internals. I've not seen a valve move only to the halfway position, usually it either moves or it doesn't (does not mean it can't happen though)
If you can hear it click, the valve is most likely just gummed up and could be, rust, fuel gelling (if it's cold enough outside) ice from water in fuel. The same things can also affect the fuel filter.
Your problem was probably the small leak in the supply line. I had the same exact problem, a small hole had worn in the metal line and it was sucking air but it wouldnt leak enough fuel to notice during parking.
If your valve is screwed up you might try running some fuel treatment to clean it up.