[Fishhook]

Well on the way home from work the other day the motor started loosing power and the check engine light came on. Didn’t think too much about it but before I got home it kept loosing power, and before I got up the last hill to the house it would hardly run. I checked the fuel pressure as it felt like it was running out of fuel and it was showing about 40 to 50lbs at best, also the fastest the motor will run is about 1200. The pressure is not steady and fluctuates a lot as the diaphragm pumps the fuel. It also has a half tank of fuel. The code reader I have won't read the Check Engine Light code so I'm at a loss as to what that is and it makes me think the high pressure oil pump may be going as it is making a lot of noise too but that also could be from no fuel in the injectors.

So the bottom line is I think the high or low-pressure side of the pump went out and it just can't get enough fuel to get out of its own way. Any other thoughts??

 

[BIGBEAN]

There are no cel's related to fuel supply. More then likely you have a hpo problem, start with IPR orings next would be change the ICP.

 

[Fishhook]

I unplugged the ICP and it didnt change anything so I think it is in the IPR or HPOP. I'm getting ready to pull the HPOP and IPR to swap with another (an early 99) I have and we'll see if that fixes it. Then I'll check the fuel pressure and see if it still needs replaced. Now it's time for a little research on swappping them.

 

[Krogg]

Were in southwest ohio? Im in louisville, and have full diagnostic scan tools. no problem for me to pop in and check it out for you

 

[Fishhook]

Krogg, I'm just north of Cincinnati Oh. just off of exit 32 on I-75. If you want too give me a call on my cell (513)292-4165 and we can chat first, or anyone else who might have an idea. A scan tool definately would be a big help right now since mine don't speak diesel. I took the IPR out and the O-ring is in good shape so I'm gonna stick in the new one in case it is jammed open with crud or something and maybe swap HPOPs too. The new HPOP has around 160K on it but it was running when I took it out of the other motor so I may be in luck. Thanks in advance for the help

 

[Krogg]

ill be on my way at 6pm tonight from louisville will call when heading out for a final direction unless there is some other local who can chime in and get r done

 

[Fishhook]

I swapped out the ICP, and the IPR and solenoid and no change. Scanning it has turned up some interesting things. We checked the computer for codes and got codes 1280, 0334, 1212, & 1211. Basically it didnt see the ICP sensor, ICP was out of range, the injection pressure was intermitent low, and the CPS signal was intermitent. Also while scanning it we noticed that while the truck was setting not there (key on) not running that it was getting rpm signals and ICP pressure spikes. Also when we tried to start it it wasn't seeing rpm signal and when the computer called for injector pressure the PCM didnt send a signal to the ICPR. So all in all I think I got a goofed PCM. I guess I will have to find a PCM to swap out to verify this.

Krogg, again thanks to you for coming up and helping out!!

 

[Fishhook]

Well the replacement PCM didnt work so I guess it's the HPOP, I knew I should have replaced it the other day. Oh well you live and learn. /ubbthreads/images/graemlins/shrug.gif

 

[tallfarmboy]

I don't think I would order a new HPOP without doing some more diagnostics first.

Find a gauge and see if that is your problem. Also, take your VC's off and see what it looks like under there while you are cranking. You HPOP might be fine, but you might be losing HPO pressure somewhere, Blown O-ring, bad injector, something like that...Pop the VC's and look for oil while cranking...

Good luck with your repair,

TFB

 

[Fishhook]

So far I've been lucky and have already had the spares on hand or could borrow it.

The main thing I'm seeing is no HP oil, unless both the ICP's I've tried are bad, I am guessing that the HPOP is gone out but a blown o-ring would do the same. I also have the HX crosover mod so if one side goes then both will die. I need to cap it off to see if I can get one bank or the other firing. If you've had a blown o-ring before does it let go all at once or does it slowly die over a mile or two with a steady loss of power??
Thanks for the help.

 

[Fishhook]

Now that I've gotten the HX mod off and checked the pressure in each head I find out that there ain't any oil pressure. HPOP on the bench waiting to go in as soon as I get a free minute. Uh, make that a free morning. Or maybe a bit more, the way my luck has been going it will take twice as long as it should.

 

[dave1957]

If you still aren't getting a rpm signal to your PCM it won't start no matter what you do to the high press oil system. Not sure what scan tool you were using. ICP press spikes and rpm signal at KOEO, and then none at crank would make me want to check 5V VREF at the ICP sensor at KOEO and at crank. Rule out that it isn't(VREF)shorted to ground or sig return circuit. It will not run with a shorted VREF circuit. If this is not the case, disconnect the IPR connector and apply 12VBAT and ground to your IPR valve. Then read your pressure output on either output lines with the other line blocked off when cranking. I would assume you checked your low press pump output which supplies your HPO system. If you have no HP oil pressure with Aux power supplied to your new IPR, either the pump is bad or the drive gear is loose/not turning. Applying Aux power and ground to your IPR valve is important, especially if your pressure is zero. A good HPOP should jump the press gauge to +2500psi. Good luck

 

[Fishhook]

Dave, the scan tool we were using was a MATCO. The weird part about it was that it wasnt seeing the RPM signal on the scan tool all the time but the tach was moving when cranking so I dont know what that was about. I will swap out the CPS too to see if it makes a difference. I will try your suggestion and see what they do too. Thanks for the info.

 

[Fishhook]

Well after applying 12V directly to the IPR solenoid and getting 0 PSI on the guage I am convinced that the HPOP went out. I wish there were more hours to the day. /ubbthreads/images/graemlins/shrug.gif

 

[Fishhook]

Further testing of the HPOP revealed it put out over 3000PSI with the IPR at 100% so I can assume it is good. Does anyone know of a way to flow test the HPOP and how much is it supposed to put out?? Now the last thing I can think of the problem being is the o-rings for the injectors. I guess this is as good a time to put in the AD code injectors as any.

Any one want a set of AA code injectors for cores?? /ubbthreads/images/graemlins/biggrin.gif

 

[sellwithsam]

Greg,

You've pulled the VC's and checked harnesses and connectors?

Sam

 

[Fishhook]

That will come on my next day off. I cant think of any other reason that I cant get any oil pressure in the heads other than a bad O-Ring.

 

[RickHredf250]

Trying to catch up here...
Did you crank while watching the oil returns on the injectors? I had one stick open and killed the engine. Hooked up gauge no HPO. Isolated the problem bank with gauge and then pulled VC to watch oil drains. Found one just pouring way more than the others. Pulled injector, took it apart found nothing. Put it all back to tegther and started right up, no problem since. Must have been some crape get caught in it from the engine rebuild.
Rick H...

 

[dave1957]

If the HPOP deadheads to 3000psi it's enough to start, do double check reservoir oil level. Bank isolation tests shold now be done. Install your gauge in either bank and reconnect the HPOP supply line into that same head. Block off the other supply line. Hook up your IPR connector and crank it. If you get low or no pressure into that bank, that bank is suspect for a leak. However I would jump aux power into the IPR to verify. Do the same for the other bank comparing pressure readings at crank. I am not completly convinced you have a UVC leak. Loss of signal to your IPR coil will cause misdiagnosis, verify that you have it. It should always have 12VIGN when keyed on. The low side of the IPR coil is pulsed by the PCM during crank.
I only caution you on the IPR because I am not clear if you had checked it when the scan tool was hooked to it(KOEO test). A pressure reading of zero at the head with a pump that deadheads ok throws big red flags up to me. Making me question whether the IPR is getting power and ground at crank. I hate to see you overlook something and do a lot of unnecessary work.

 

[Fishhook]

Rick, that is a good posibility on what happened to me. I will check it out and post the results.

Dave, I was going to do that and isolate the problem but I figured it would be a good time to stick in the new injectors but then I got to thinking about WHAT IF. I think I will isolate it to see where the problem is and then swap injectors later and I will check to see if I get 12v to the IPR. I agree with you about the IPR, if the pump is good I either don't have signal at the IPR or I got one heck of a leak in one or the other heads, did I mention I put 12VDC straight to the IPR?
Thanks again for the help.