Intermittent Problem

[pcs]

I've got an intermittent problem. My 1995 7.3L diesel runs fine, then just dies. And it dies like its running out of fuel. Once it begins to fail, feathering the accelerator has no response from the engine.

So, I've replaced the fuel filter, dropped and cleaned both fuel tanks, bypassed the fuel tank selector valve so that the rear fuel tank is feeding fuel to the lift pump without going through the selector valve, replaced the fuel lift pump and replaced all of the rubber hoses in the fuel system.

Tests at the schrader valve on the fuel filter housing show a consistent 58 lbs pressure.

On a recent test drive of 20 miles it ran flawlessly. The next day, it ran for 1 1/2 blocks and then died (again apparently from fuel starvation). Except that when I opened the fuel filter housing it was full of fuel.

So, I'm starting to think that it's either a bad main pump, the computer or an electrical issue of some sort.

Based on this description, do any of you have any suggestions what might be the problem? Or can think of any additional tests I can run to determine the problem?

Thanks,
pcs

[Chop]

Have you changed the cps yet?They are famous for random killing of engine.

[pcs]

Haven't changed it yet. I read an article that mentioned that low oil level in the crankcase can cause the engine to shut down with similar symptoms because there is insufficient high pressure in the oil to open the injectors. So I'm checking the oil level first.

Where in the engine compartment is the cps located? And what does it look like? Just so I'm sure I'm changing the right sensor.

[B4SouthernMiss22]

Yeah ill be willing to bet its the ole CPS sensor

[Chop]

It's mounted on the front of the engine ,girlfriend side just below waterpump.All is needed a 10mm wrench and of course a new crank position sensor.wiggle old one out,install new one.

[Mdt1992]

yeah id definatly check the oil level first being its free, mine had a pretty good oil leak and would shut up a couple blocks down the road, but once it warmed up would run fine, ended up finding it to be 6 quarts low or so, found the leak and fixed it pretty quick after that, then next guess would be it sounds like the cps is going

[pcs]

Thanks for all the input. It turns out to be the oil. It was LOW! Changed it and the filter and the truck's been running like new.