1996 PS no start need a little advise from the pros

[rmdoug1]

Hello Folks,
Glad to meet everyone. I am a regular on a few boating sites and came over here seeking a little help. I have a 1996 F-350 P/S diesel sitting in my driveway. belongs to a good friend of mine. I am the local mechanic for most of my friends, I have been around vehicles all of my life. Although I am not a P/S guru, it would seem I need one now.
Here is the issue.
He was sitting at the fuel station in line waiting to fill up, not on Empty either, truck shut off, has not started since. I had my Dad tow it to my house and here is what I have done.

1. replaced CPS, using Echlin from NAPA replacement part.
2. it has the standard mechanical lift pump behind the fuel filter, it has over 10 psi at the schrader valve using a standard fuel pressure gauge to test.
3. completely charged the batteries, before testing to ensure full cranking capacity
4. using a hyd pressure gauge in one of the head oil ports HPOP is pushing 2000 PSI at fast turn over.
check each and every fuse individually, at both locations
5. checked and replaced relays.
checked harnesses for chafing
6. scanned engine..NO CODES
7. tach moves a little while cranking
8.WTS light functions normally
9. Engine light cycles for a very short second when turning ignition on.
10. engine is full of oil, slightly over full????
11. removed, checked and replaced oil filter to check for internal signs, good compression.

so....
What do you think????


Thank you in advance for your help,
Doug

[tweeter]

correct me if I am wrong but I have a 2000 psd and if your hpop is like mine you need 18000 psi to fire the injectors. good luck also check injector driver module (IDM) located on drivers side fender towards the back of the fender

[97powerstroker]

i thought oil pressure only needed like 500psi to start?is the fuel bowl full?under valve cocer harness burned? idm def a possiblity.

[sldghamr]

Originally Posted by tweeter

correct me if I am wrong but I have a 2000 psd and if your hpop is like mine you need 18000 psi to fire the injectors. good luck also check injector driver module (IDM) located on drivers side fender towards the back of the fender

an IDM that is failing would mostly likely cause a loss of power, throw codes and cause the check engine to come on. check anyway, though. an IDM is a Ford only item. the IH version will not work cuz of programming differences. see about going to a wrecking yard.

[tweeter]

well im not sure about pre 99 psd but mine needs 18000 psi to fire i believe yours is the same

[BudDog]

I thought they only ran 3000 psi running hard. 18000 sound kinda high but I could be wrong about what I thought I read.

[tweeter]

A little history Ford introduced the first Power Stroke diesel engine in 1994. It was among the first of a new generation of medium-duty diesels with direct injection (DI), where the fuel is sprayed directly into the combustion chamber. Originally developed by Caterpillar as the Hydraulically actuated, Electronically controlled, Unit Injection system, otherwise known as HEUI, it has a single injector above each cylinder instead of a pump-line-nozzle system. Each injector is supplied with fuel at relatively low pressure, and the injectors themselves generate injection pressure. Mechanical unit injectors like those used on large engines are actuated by a lobe on the engine's camshaft, working through a pushrod and rocker arm.

The HEUI system uses high-pressure oil and a pressure multiplier piston inside the injector itself to generate the 20,000-plus psi needed for injection. Solenoid valves are used to control the high-pressure oil circuit, which tops out at about 3,000 psi. This means injection timing and duration can be controlled with a computer instead of a camshaft.