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Discussion Starter #1
Hey guys, name's Josh. Im a brand new member to the site but have had my butt saved by reading on here numerous times over the years! I have an early 99 super duty with 280k miles. This truck has literally been one fix after another for about 7 years now but it has taught me alot and I just cant seem to part with her. Anyways onto my problem...... The truck had all the symptoms of a UVHC going bad even though years back I replaced them both with the new style ones that are molded all together. It began to shake one day at a stop sign but would recover and be fine for a few days. It did this a few times before the shake became constant and wouldn't go away as if I had a single injector going bad.(new single shot stock injectors 5 years ago w/ dptuner to run stock) I planned on checking replacing the UVHC but was waiting till the weekend. Then going 65 on the highway she started to shake really bad and steadily lost power. I made it a little ways off the ramp before she died completely. After several attempts I got it started but rough and was able to make it 4 miles back home on back roads. She cut off at least 6 more times in doing so making it varying distances each time. So heres what I've done so far:
Unplugged passenger side uvhc; little to no change at all. Did the driver side and the engine shut down soooo...
I replaced: IDM, UVHC, exterior pigtail harness to UVHC, fuel filters(2), and IPR.
I ohmed the UVHC at the valve cover and everything was sat. Ohmed the IDM harness and they all came back good as well.
What on earth am I missing here!? I'm at the end of my knowledge and getting close to the bottom of my pockets. Any help would be greatly appreciated as this is my daily driver and she wont make it more than a quarter mile at a time now. I should add the SES light only came on once and went away when I was losing power on the highway with my foot to the floor. Also in case it matters the fuel tank is harpooned and the fuel pump was replaced about 4 years ago as well with a bosch and a pre pump filter(baldwin) added. The oil is also new and full.
 

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Could be the harness is shorting out where it crosses over the driver's side valve cover. The injector circuits are on the bottom of the bundle, so are the first to wear thru. Pull the connector off and check the bottom side of the harness.
 

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Discussion Starter #3
Thanks for the tip but I looked for that rubbing and didnt see any. Wouldn't ohm testing at the harness connector to the IDM eliminate a shorted out wire between IDM and UVHC?
 

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Discussion Starter #4
Could the IDM from autozone be bad and giving me the exact same conditions as the old one? I actually had the IDM go bad and kill the power to the passenger bank so I replaced it a few years ago. That experience is why I suspected it again this time and replaced it without testing it but I suspected wrong unless the new one is bad and coincidentally giving me the same issues. Thoughts?
 

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Could the IDM from autozone be bad
Possibly. It has happened before to get a bad out of the box part.
Do you have a scan tool you can hook up to? You should have codes if the SES light has been on (even if it's not currently lit). It takes a PowerStroke capable scan tool.

If you checked your wiring with one probe of the meter on ground and didn't find a short then you're probably OK.
 

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I am curious, how did you come to the contusion that you have an electrical problem with the fuel injection? With your experience and this truck I imagine that you have a scan tool. Are there any codes that are directing you or is your diagnosis purely symptom based?
 

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Discussion Starter #7
Thanks for the responses. I have no scan tool just basing it on the symptoms. I thought if I unplugged the harness and nothing changed then that's the side with an issue and would be electrical? Also in working on it I have disconnected the batteries so I dont think the code is stored in there anymore.
 

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When you say the tank is harpooned did you also do the Hutch mod which eliminates the screens and mixing chamber? (The harpoon is just cutting off the fill tube)
 

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Disconnecting the Harness on one side is a valid diagnostic procedure, but only lets you know which bank the problem is in.
All it takes is a crank attempt to get codes, so again, GET IT SCANNED. Otherwise you and everyone is shooting in the dark.
 

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Discussion Starter #11
Yeah I know we all are shooting in the dark and I appreciate everyone's help. I was just hoping not to have to pay to tow it to a place, get scanned, and towed home.... because After replacing the IDM last weekend I took it for a test drive and couldn't get it back home. At about 1030pm I coasted into a parking lot of a closed facility(virus) with a huge empty parking lot with construction next door utilizing the lot as well and parked her till 6am the next morning. The shutdown facility with a thousand spaces towed my truck($145 oh well), but the real kick in the nads was I couldn't get it started at the impound so I had to pay to tow it home($85). Neither towing distance was more than a half mile tops! All I can do is laugh because it's my own damn fault but geewiz. It is what it is! Thanks guys I will post back whenever I find the solution. I will try to have it scanned tomorrow or tuesday.
 

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Discussion Starter #12
I'm beginning to think an injector or two have failed with only 30k on them. I cant remember the name of them right now but they were from the company everyone reccomends. I dont seem to have the greatest of luck so it wouldn't surprise me if they have. Haha. Anyways besides an injector and wiring could a bad ICP give symptoms this severe? I've unplugged it and noticed no change but it definitely was coated in oil yet the ses light only comes on when I unplugged it.
 

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For a cheap scan tool look into ForScan to be used on your android phone. There may be a download for a iPhone also. Do a search for ForScan Lite to find out. Then with a ELM 327 adapter which works off of bluetooth you will be ready to go.

 

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Discussion Starter #14
Thanks bugman! I thought AE was the only way to go. I guess I've just always looked past any phone app without looking into it. I had no idea! I will definitely check that out this evening! Since my last post I've pulled the valve cover off the passenger side and with the engine running unplugged each injector, one at a time. A definite change when I unplugged and replugged #1 and #3 but no change at all for #5(plugged or unplugged) and no audible change when #7 was unplugged but a very slight change when I plugged it back in. Am I getting warm yet?
 

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Discussion Starter #15
Please swap #1 for #5 and #3 for #7 in my last post. I looked at the layout wrong. It's the 2 forward most injectors I'm looking at.
 

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If you have a multimeter, check the resistance of each injector solenoid. Could be the solenoids on those injectors are bad.
You should see less than 5 ohms across each solenoid. If you find that, you can just swap the solenoids with replacements.

I'll bet you've already spent more than the cost of AE, but Bugman's suggestion of ForScan is also an option.
 

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Discussion Starter #17
Thanks again for all your input! It seems the solenoids are fine, all are around 3-3.5ohms. I just looked up the AE tool and am kicking myself! I dont know why I had it in my head that those darn things were more than $600! If those 2 injectors arent firing they are more than likely bad, correct? Or could a fuel pressure issue or ICP be causing them not to operate?
 

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If the wires are long enough swap them with the working injectors and just watch to see if they are spitting oil when you try to start.
 

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Discussion Starter #20
All 4 injectors out. Very dirty/cruddy tips but I dont see any blatant o ring failures. The top hard plastic ring looks warn/beat up on a couple but I wouldn't think that's a seal. Ever have orings fail that look fine with these things?
 

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