When this first started to happen, I pulled codes and it came back with water temp sensor, and air temp sensor circuit failure, so I replaced both and it continues to happen.

When Its cold these sensors along with the relays malfunction and wont send power to the fuel pump on the rail. usually I can get her started by wiggling the wires on the relays, cleaning them, unplugging the sensors and relays, etc.

But today it started right up and about 30 secs later while I let it warm up, it stalled and wont start again. Ive tried my usual tricks to get her going, even wiggling the wires on the pump itself and I switched the relay with a (old not new) spare one. Still nothing...

My friend and I bumped the timing last night, I dont think this would have anything to do with it, but I need some input here, What can I do to permanetly solve this problem!!! I missed class and a quiz that was in class today because of this SOB, please help!

 

You will have to test her to find the problem, there is no other way short of throwing parts at her. Begin with checking for a strong spark, and good fuel pressure...there will be a quiz on your progress

SBFTech.com TFI Module/Hall Sensor Testing Procedure

Part 1 -Ford Ignition Module Test. Fender Mounted Module (ICM).....Read carefully through all the pages of this link

 

Thanks, Im looking into it now

 

Was it up to full running temperature when you pulled the codes? KOEO or CM codes?

Those sensors failed or not wouldn't stop the fuel pump from running when first turning the key on.

Sounds like you have a bad wire or bad connection rather then any other issue.

Again suggests a bad connection, might suggest a ICM or PIP however that wouldn't stop the pump from running for one second after first turning the key to "run".
Might be an issue with the computer itself, to test pump and related circuits ground pin marked "Fuel pump" in EEC self test port, do so with the key in the run position, selected pump should run continuously.

EEC test port pinout shown here Fuel Injection Technical Library » How To Run a Self-Test

Bumping the timing wouldn't cause issues such as you describe, jumped the gun doing so perhaps but no not directly the issue.

 

bought a new code ready today because my old one quit working, heres what came up:

21:engine coolant temp sensor (replaced less than a year ago)
24:air charge temp sensor (replaced at same time as coolant sensor)
31:EGR valve position sensor
67:improper signals being recieved from neutral switch
82:thermactor air bypass
87:fuel pump relay

codes this time were NOT pulled at normal operating temp. I also went and bought a new fuel pump relay hoping that was it, still nothing...

I ran a wire to the fuel pump itself from another 12v source and it works, so I assume its somewhere in the wiring between the relay and the pump.

Havent checked the wires yet cuz it was cold and dark, so Im going to get back at it tomorrow

I could hear it kick on when I put the aux power source to it and could hear gurgling from the fliter(?) thats behind it along the rail. Could the filter be clogged up? Ive never changed the filters on it before, wanted some input before I spend more money that I dont have....

I also checked the valve there at the back of the fuel rail, nothing came out when I had my buddy try to start it. (I didnt have the aux power run to it at the time though)

 

21 and 24 both normal when not up to temp for testing.

31 test the EVP Fuel Injection Technical Library » EGR Valve Position sensor (EVP) More on that if needed.

67 Manual trans? IIRC you gotta hold clutch pedal to floor during test, if not held to floor that be the resulting code. Someone with a manual could verify perhaps? I'd need look it up know for sure.

82 does it have TAB and TAD solenoids? If not, someone removed the air system, that'd be reason for code.

87 fuel pump circuit failure, basically telling you its "open". You'll need to trace that one down.

 

Ive never gotten the clutch code before when pulling codes, and yes its a stick. I dont know what teh TAD and TAB solenoids are, but the A.I.R. pump thing under the alternator is still there but all the lines have been cut off and the system was taken out before I bought the truck.

 

well Im probably going to have to trailer the old girl home to the mechanic. I traced the wires from the pump to the relay to the computer, can find any obvious shorts. Pump works when I run other power to it, and fuel is pumping at least to fuel rail. and its getting spark and wants to run off starting fluid. My mechanic said computer is probably last place to look for the problem, plus it was replaced 2 yrs ago with a new one. I also replaced the fuel pump relay but that wasnt the problem.

anyone got any idea?!?!

 

Possibly the dash mounted tank selector switch?...trace the 12v now, it is interrupted somewhere...run a short jumper wire on the test plug #2 to #6 so there is continuous power to the pump for tracing purpose

 

Ok Ill try that tomorrow. But I just got her to run, but only for a few seconds and then once the fuel rail runs out of fuel it dies. My buddy says its the timing because we were messing with it. So hopefully tomorrow we can get her straight

 

I was told that it's the computer 2% of the time.

 

Ok, so im about to lose hope with my mechanical capibilities. I found that both the HP and LP pumps are pumping, not sure if they are pumping as much as they should be though.

i used to be able to hear the HP pump prime when I turn the key, now I cant unless I put my ear below the truck. fuel is also coming out from behind the reservoir and coming out all the way to the rail.

I replaced the filter, I pulled it off and looked like muddy water pouring out, so it def needed a filter (ive owned the truck for over a year and a half and never replaced it, opps)

Still not staying running though (couldnt get her to start after I replaced the filter, i dont know if fuel was able to reach the rail or not after all that emptying out)

runs for a couple secs then once the rail runs out of fuel it stalls. going to mess with her a little more tomorrow, then probably loading her onto the car trailer and get her ready to be towed home to the mechanic....

 

well still no luck, alternator checked out fine, Im taking the bed off today to get into the rear tank and check the pump.

My filler neck might be to blame, so my friend tells me. Its hard putting fuel in, only about 3 cents at a time now, he thinks my vent hose thats inside of the filler neck might have come off causing a vaccuum problem and thats whty it wont stay running.

I also tried using my front tank, but still no go.

Could the filler neck really be to blame? Does anyone have a cut away view of the filler neck (rear tank).

Im going to check the neck and pull the pump out to inspect it.

If thats not it, shes being trailed home (hour and a half) to my mechanic so he can fix it.

 

You need to go to napa and get the eec relay plug. They are the only place i could get one. Do you have a check engine light when it will not start?

 

Have you considered just installing a fuel pressure testing gauge on the fuel rail...would answer a basic question