I have an 88' F250 and several months ago I was having problems starting. I installed new glow plugs, cut and plugged the injector return line to the filter , and charged the batteries. Then my truck started and ran nicely. Between bad glow plugs and fuel flowing back to the tank, I thought the problem was solved. But, after about a week it wouldn't start again. Last week I tried getting it started but didn't have any luck. I figured I should replace the injectors, o-rings, and return lines. Any other suggestions? Also, does a cut and plugged injector return line cause the injectors or o-rings to fail prematurely?

 

Is the GP controler working properly? Do you have fuel going to IP?

 

The "wait to start" light comes on for about tens seconds then shuts off. I have plenty of fuel coming out of the schrader valve on the filter head. Should I loosen the line going to the ip or should i loosen the return line of the ip to check for fuel?

 

Take the line off the pump. Wondering if fuel filter is plugged.. or hose gone bad.

When the wait to start light comes on does your headlights dim.

 

Charged the batteries.......... how fast was the engine turning........if you can count RPMs its way too slow.......... need 200rpm.

 

10 second wait to start light is way to short . it should be more like 15-20 seconds. what type glow plugs did you put in?? i bet you have some bad glow plugs.

 

Yep, what brand of plugs did you buy? As stated a million times.
Use ONLY Beru/Motocraft plugs.

Do a search on GP testing.

And no, plugging that return line to the filter should not cause any probs.

 

I second the glow plug controller. Check the glow plug harness with a multimeter after you turn the ignition key for the glowplug light to go out. If you have 0, probably the controller? Seems to be my problem with the same issues. For what it's worth.
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1988-F250-7.3 Diesel-C6 Auto-3.55 rear end