My thoughts exactly.

 

not sure on the 88 7.5, is it mass air flow?
if so, it will not run if the MAF sensor is not reading air flow.

 

Where might that sensor be?
On the throttle body?

 

this the thread your refering to?
https://www.ford-trucks.com/forums/1...uel-reset.html

 

what is the fuel pressure at the rail? the pumps may be running, but not supplying enough pressure to fire the injectors.

 

No, the 88 would be Speed Density.

 

Thats it , funny you found it I looked at every post I ever started and it wasnt there.

Must have been a glitch.

 

What and where is a speed density?

 

Speed density doesn't use a mass airflow sensor in the intake tube. If your intake from the airbox to the intake on the moor has 2 tubes running the whole distance then you Have the speed density

 

Speed Density is the older version of EFI that Ford used. Mass Air Flow takes a reading of the amount of air entering the engine and adjusting the amount of fuel to match accordingly. It allows the engine to adjust to changes, and keep itself in tune. Speed Density uses a narrow preset calibration range from the factory of what the amount of air entering the engine "should" be, and can only adjust the fuel amounts slightly to match that range.

 

And that could make it not run?
It doesnt run badly .....it runs good when your pumping it.

 

Speed Density is not a specific sensor, its a system. If there was too much modification done to the engine, it would not run. By modification i mean bored, stroked, or aftermarket heads. just putting an exhaust on would not cause problems.

 

Nothings been done the truck is "old man stock"

 

than it should run fine

 

Thats kinda what I figured but it doesnt ..........unless you pump it until your legs sore.