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Discussion Starter #1 (Edited)
Folks,

96 F250.

I have had three bouts now with this same symptom. First time it died the issue turned out to be the fuel pickup was gone so it basically ran out of fuel. Replaced pickup and put in a new fuel tank while in there.

Fast forward a year, running fine, and just died running down the road. Fuel tank was below 1/4 tank. I added fuel, added fuel to filter housing twice and finally got it running. Started to think the darn fuel pickup was bad again. A few days later it started to do the same thing but was just a few doors from home and got back to the driveway without it actually dying.

After reading a bunch of threads, I replaced CPS and ICP sensor. Decided to check glow plugs because it was always hard to start when cold. All four connectors from harness to valve covers were melted at glow plug wires. Replaced all glow plugs, under valve cover wiring, and spliced in four new connectors to harness. Engine fired right up and ran great.

Fast forward 3-4 weeks. Drive to work fine. Leave work and engine seems to run a little rough then smooths out. A few miles later it dies. Fuel is below 1/4 tank so I add fuel and check filter bowl. It's fairly full. Will not restart... dozens of tries.

I hook up AutoEnginuity. Buzz test works but get a P1278. During starting I have 3400PSI oil pressure and ~50% duty cycle. Fuel filter bowl is full.

Seems like I have fuel, oil pressure, and injectors. Any ideas?

Thanks,
Chris
 

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Check your fuel pressure.

I NEVER go below 1/4 tank in either tank. Even with pick up tubes at the bottom of the tanks it still manages to suck in air. So at 1/4 level switch to the other tank then when it gets close go and fill it up.
 

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Discussion Starter #4
Thanks. Will check fuel pressure. Pump replaced during first instance of this issue...

Chris
 

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Your fuel pump is actually two pumps in one -- the first(low pressure) sucks from the tank and pressurizes the filter -- the second(high pressure) draws from the filter and pushes into the fuel rails

One pump can fail while the other is fine -- if the filter housing is not full, the low pressure pump may have failed - or there is restriction in the fuel lines or air getting in (critter damage) or loose/cracked hoses
 

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Discussion Starter #6
Thanks Hydro. Fuel pump is only a year old. The filter bowl is full. Will be checking fuel pressure next.

Chris
 

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Are you at a crank- no- start now?? You get any smoke when cranking??
 

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Discussion Starter #8
Yes, crank no start. 3500 PSI oil pressure and 50% duty cycle on CPR reading during cranking. I am not getting clouds of smoke, but yes some smoke from tail pipe.
 

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Showing RPM on the dash while cranking? Voltage present in the cigar lighter plug? - Voltage on the system while cranking needs to be above 9 volts

You have AE, does it show RPM and sync?

7.3 is not my strong point, so hard to give detailed instruction -- could pull a valve cover and check for oil discharge at the injectors - indicates they are operating

Cold where you are? glow plugs working?
 

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Discussion Starter #10
Did not check tach while cranking. Will check all the above. Not sure what "sync" is... It's not cold now (60 degrees) and when it last died it was up to temperature. Glow plugs are new and solenoid is new. I'll verify it's working but it was fine before it died.

Thanks
 

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Then likely a short in the harness ...somewhere -- back at the CPS connector possibly -- have to look all along the harness
 

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Discussion Starter #12
Tach is working during cranking. I checked fuel pressure at schraeder valve on filter bowl right after cranking(my pressure gauge is broken so this was with a tire gauge). A tiny hiss but no real pressure. That's the low pressure side correct? Shouldn't there be pressure there held after cranking?

If my CPS connector were bad, what is the failure mode? AE says I have tons(3500psi) of pressure during cranking. Past experience says it's under 500-600 at idle as I recall...
 

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Check the pressure while cranking. I'm sure the pressure will bleed off quickly with the pump not pumping. Cheers!
 
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Discussion Starter #14
Hi folks. I'm finally back to this project. Truck has been sitting for 8 weeks. I tried to check fuel pressure. I got nothing. Opened filter bowl. It's now bone dry. Can it drain back to tank? It's not on the ground.

I also checked wiring to ICP. Pins out to engine harness connector and neither wires are shorted to ground.
 
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