On Thursday, my truck suddenly died (similar to someone cutting off the fuel supply). I had just filled the truck 20 miles earlier. I had the truck towed home, where I found I wasn't getting any fuel pressure (at the test port). I replaced the mechanical fuel pump, and the fuel pressure returned (up to 60 psi while cranking). However, the truck still would not start. I plugged in my scanner to see where I may be going wrong. Here is what I found:

ICP was around 3,000 psi (good)
V PWR (during cranking) holds at 11.75 volts (good)
RPM was around 145 RPM (spec says anything above 100, so good here too)
FUEL PW read 0.210 milliseconds

The FUEL PW is my concern since this isn't any part of its normal specs. However, I am at a total loss of what may be the problem.

Could it be the IDM, even though no code for it?

I have changed the CPS (just to make sure).
The only code is P0472 (EBPV low, I know its low, its gutted).
I have spent nearly the entire Labor Day weekend trying to solve this.

 

How long did you crank the motor after the pump was replaced? when you empty the lines it takes about 30 sec to get enough fuel back into the system to get it to fire. I know when you work on injectors its recommended to crank for 30 sec each time then pause to let starter cool then crank 30 sec more if it doesn't fire sooner.

 

Doug, ... Welcome to FTE.

Sounds like you have a real tough problem going on there. Since you have a scanner can you do a BUZZ test. That should tell us if the IDM is working or not. I believe your problem is in the PW parameter, as you suggested, and for some reason it is low. From my documentation ...

Pulse Width; 0 ms means no sync, 1994-1997 .42 ms indicates that PCM and IDM are in sync (on 99-03 it should be .60 ms) and the PCM is waiting on the ICP to reach the minimum pressure. When min. ICP is reached PW should change to 1-6 ms

After the BUZZ test, if it works, scan for codes as that is when the IDM will report any codes it detected during the test.

 

I have cranked the engine multiple times of 20-30 seconds.

I do have several scan tools. They do not offer me the ability to do a buzz test on this engine. The one I bought today, will go back to the store because of this.

 

IIRC , The 3000 ICP is what the PCM was calling for ,I suspect the IPR was not responding. We need to see what IPR DC% is while cranking

 

The IPR DC% is 40.0 sustained while cranking. It started out at 14.9% before cranking, and peaked out at 59.8% right when I first started cranking. It went to 40.0 after about 2 seconds of cranking.

 

The IPR is not responding(stuck open)60 % DC is the PCM commanding full closed & not seeing expected ICP .. .


Or there is an O ring issue (IPR ) easy & cheap test, Or an injector O ring .. My wag is the IPR is stuck...

 

I just replaced the IPR (with a remanufactured one I bought online) about a year ago. And since I'm seeing the IPR vary, I'm leaning more towards the o-ring issue. You said it is a easy & cheap test, how do I do that?

 

IPR 's cannot be re manned .. As for the O Ring, pull it & examine the small O ring on the end ...

Keep in mind what Jim said about the IDM ... If you actually have 60% IPRDC & 3000 PSI ,, IDM may well be toast ...As he said , a buzz test will help determine if it is working ...

 

I appreciate everyone's help and quick responses. I got the problem solved. Apparently when I pulled the fuel regulator off of the fuel filter housing, I lost the o-ring. When I went to check out the IPR today, I noticed the lake of diesel sitting on top of the engine. I had a neighbor crank the truck while I was watching and saw where the fuel was leaking from.

 

i guess there's first time for everything

 

Glad you solved de problem, but you didnt say anything about the FPR LOL JK.

 

Hood open , testing , never notice fuel spewing every where , & cannot pool up below the IPR .. Not to mention FPR leak can't cause 60% IPR DC ...

 

Rick do you think it could be the IPR or ICP wiring? Maybe when he was fixing the fpr he wiggled the wires and it's a temporary fix