You can snip a relevant portion of the graph to point out an issue or ask for feedback. Attaching the CSV file to the post is good as well, so we can scroll around the data and give you more eyes on it. You can attach the excel file if it will fit - sometimes it gets a little big. A pdf is ok, but less useful, since we can't play with the data. But we'll take what you give us. Thank you for what you've captured so far with all this data - it should lead us to a solution.

Your text file is highlighting 4 injectors, 2 on each bank, that have electrical issues. Recommend checking the wiring at the valve cover connectors - Injector coil pin to Injector common pin, on each. You should see about 3 ohms.

(OK) [22:42:09.122] KOEO Injector Electrical Self Test has been started
(WARN) [22:42:24.823] Test completed, found DTCs: P1272, P1277, P1275, P1278

The buzz test says 2, 5, 7 and 8 are not working - high to low side open circuit. Did they sound ok? These intermittent issues can point to loose/wornout harnesses. Consider checking/replacing the UVC harnesses on both sides, and checking continuity on the valve cover to 42 pin connector harness. If that's good, check from the 42 pin connector to the IDM. Do this while wiggling the harness wires.

If the harnesses are in good shape electrically, that IDM might need repair. You could pull it and inspect it for water intrusion, corroded pins. Check for burnt/bent/corroded pins on each of these connectors in the signal path, actually.

Curious that the contribution test pointed to #6, but the electrical tests point to 4 others. Reminds us to take contribution tests with a grain of salt.

 

Interesting, I do remember checking the UVC harness and 42pin connector back when I was doing the Hutch mod and fuel system fixes. I remember there being a guide can't remember if it was in my Factory repair manual or somewhere in FTE . I'll have to see if I saved it in my files.

In the meantime I think I was able to attach the Exel file of the PID log using a family members PC , please let me know if you are able to access it?

 

I can access it. Data looks normal for an easy drive. Recommend adding VSS to your PID list so we can see your vehicle speed.

Interested to see a WOT run, but it's looking like the issue is electrical, and may not show up in the live OBDII data. But you will have some good baseline information.

 

When I logged that trip I had gotten up to about 70mph and was between 50-70mph on a long stretch. The rpm of course would lower as it shifted up. The speed limit was 45 on that road so was a little hesitant to push it more and also not sure it was safe for the engine while not running well? Maybe I will take it out on the highway next time with the VSS added.

Today I disconnected the plug to the IDM and tested for resistance from the plug through the 42 pin connector and UVCH.

Results:
#2 2.8 ohms
#4 2.8-2.9 ohms (flicker back and forth)
#6 2.7-2.8 ohms
#8 3.7 ohms
#1 2.9-3 ohms
#3 2.9-3 ohms
#5 3.1-3.2 ohms
#7 3.0-3.1 ohms

I got the same readings checking resistance from the 42pin connector through the UVCH. The resistance readings from the 42 pin connector to the IDM connector were all 0 ohms.

I then checked the terminals going to Injectors #8 #5 #7 (which had the higher ohm readings) from the 42 pin connector to the corresponding point on the end of the plug that attaches to the UCVH and they all had 0 resistance.

AM I correct to assume this means the problem would be in the VC? Either the wiring harness or the injector solenoids?

 

You should be able to give it the onions to see how the high pressure oil and boost systems perform - I would not think you would hurt anything, even if one or more injectors is occasionally not firing.

Boy, so far, you are not seeing any opens in the wiring that would indicate a problem. Still good to get eyes on each harness/connector, including the ones under the valve covers. Since the problem appears intermittent, it likely manifests itself when things are vibrating from a running truck/engine. Wiggling wires while checking readings can help find opens/shorts.

Did the IDM itself look ok? No water intrusion? Might be worth pulling the cover off of it to verify the interior is clean/dry.

Might as well take a look under the VCs and see what you find. You just did this with the injector connectors. Wonder if the connectors could be backing out at the gasket itself - had you done the 50cent mod to lock those in place? Mine had backed out just a bit before I did the mod.

 

Wow, looks pretty clean under your VC, do you drive your truck? Kidding aside, I heard about the 50 cent mod but last time I was under my VC It didn't look necessary. I will check again now that I need to re open them to test the harness.

So the #8 resistance of 3.7 ohms wasn't too high? The Buzz test specified #2 #5 #7 and #8 faults aside from #2 which looked the same as the others( 5,7 and 8 were higher). Are those within spec? or Should I still keep those faults in mind? What would it look like if the solenoids needed shimming?

Another thought crossed my mind while reading about how the IDM worked was that it needs accurate timing data from the CPS. I replaced it back when I did the Fuel system repairs but not sure which one I installed. I have heard that some are better than others.

I removed the IDM which on vans is inside the engine compartment rather than in the wheel well and offers some measure of protection from the elements but I will look it over and see about opening it up tomorrow.

Thanks for all the help so far!

 

Today I got a chance to remove my VC again and took out the UVCH to inspect. On first glance the harness clips looked pretty tight and I checked resistance on every wire going to the injectors and glow plugs. They all had 0 resistance. I could move the clips back and forth so I suppose it’s possible when the engine is running they may move but I’m in doubt about it.

Two things I did notice were oil sludge inside the passenger side connector to the outside. The driver side wasn’t too bad. I wonder if the sludge is causing a bad connection? Another thing I noticed was 3 out of 4 clips holding the wire harness to the gasket were broken. Wonder where the broken plastic went? I don’t see how that could affect performance though.

Should I clean these UVCH and then reinstall with the 50cent mod for good measure? What would be a safe cleaner for them? Also the rocker arm assembly and injector solenoids have a thin layer of sludge on them. Should I clean them?

I still haven’t opened up the IDM. I’m hesitant as it is sealed with silicone but if it is necessary I will.

 

That 3.7 ohm reading you had on one was a bit high, with 3.6 ohms being the max per the GB IDM replacement document you posted earlier. Seeing how dirty these harness/gasket connections are, could be where it's coming from.

What does the forum think? Would you clean these up? With the snapped plastic retainers, I'd be tempted to replace them, especially if working on a van.

 

I would replace them, he won't want to get back in there again and it would eliminate those from being the cause. Do it once, do it right.

 

you can use Brake Cleaner on the connectors, then dry it with the air hose nozzle.

if they don't feel good, replace them

 

Good to know brake cleaner is ok, wasn't sure if it would affect the plastic.

 

Second time this week removing the valve covers, its really not that bad on a van toughest part is setting your mind to it. Not sure it will be fun if I ever have to replace the front injectors or cups though? Turbo repairs are a piece of cake on this thing.

That said though the wiring and connectors appear to be in good shape I agree that the broken clips allowing the wires (though stiff) running freely under the valve covers kinda bothers me. Would it be a viable option to clean and reuse the gaskets and just replace the harness or is it necessary to replace all? Only reason I ask is that I recently put about a grand in suspension work and close to another grand in cooling system overhaul and concerned that if this isn't main the problem It might be another grand if I end up also needing an IDM.

I suppose this is what it means to own one of these and I guess its still cheaper than buying another truck that you know nothing about.

 

don't leave it on long enough to effect the plastic, just get the grease out.
a 10 second spray should move the grease.... then blow it out.


or, just use Dawn dish soap, that stuff is a gorilla for grease removal, and it sure won't hurt anything.

again, blow it dry, dry dry.

 

I don’t remember the whole history of your thread but if you have PCM or IDM troubles the best thing to do is send it/them to dieseltechchatt.com for inspection/repair. I have only ever heard glowing reviews of this company.

 

Thanks, good to know!