died while driving, towed home, 3 days trying and still no start

[mnmnm]

Hi guys, been followin yall 3 years and youve fixed every problem I ever had. THANK YALL!

Now I got a 2000 excursion 7.3. Around 400k miles. Has been doin the white smoke at startup with shaking (kinda like misfire) for a while. It smoothes out within 1 minute every time. Other day, left it idleing at a store, came out and it was off. Cranked back up and drove wierd... Went to 3k rpm before it shifted, od light wouldnt turn off, etc. All that smoothed out within 1 minute driving, so no worries. 5 miles later.... Died. While it was still rollin in gear, it was staying running, but once it rolled to a stop, the candles were out.

Put a new cps in it, nothing. injector drive module, nothing. #30 fuse not blown. Oil and fuel filter has 1k miles on em. Air filter cleaned at that time. Thanks to yall, removed valve covers and drivers side was almost unpluged, so took care of that.

The "wait to start" and "water in fuel" lights flash and a cadence of 60 flases per minute... I never seen that. On two occasions tryin everything, I turned the key on and they DID NOT flash, just acted normal. Thos two times, the truck fired right off as normal, ran for 30 seconds and died like I turned it off. While these lights are flashing, there is the #302 relay under the hood clicking at the same cadence. I swaped it also with a good one, but no start.

HPOP is also full, it has always had a slow leak down, so I have to fill it up at least once per oil change. But its always the 1st thing I check. Or... Yall think the o-ring inside it fillay took a dump?

I trust yall way more than ford, and dont mind sweatin, cussin, and bleedin..... But I hate losing! Anyone got a sugestion?

[airbassador]

Mine has done the exact same thing. Turned out to be the Under Valve Cover Harness (UVCH). You can just tear into it, but it would be helpful to run a Buzz test on it to verify if it's the left or right cylinder bank. I got mine for just under 30 bucks at the local International truck parts dealer, but I know Oreilly's auto parts carrys them for the same price. Make sure you get the one with the 'upgraded' connector.

What happened to me was the harness shorted out and burned, and after 2 days of driving with the truck cutting out on me, it just quit running all together.

Its an easy fix, but it will take a few hours and some patience.

Mine has started hiccuping again however a year later, and I realized it happens when it's 'damp' outside. I had noticed this last year, but upon finding the toasty harness wrote it off as coincidence. I suspect my IDM module up under the fender well is getting moisture in it, and shorted out my UVCH.

The UVCH is a known failure point, and you can bet that with your symptoms and it's not CPS, this is probably the issue. Why is debatable (thus I think it's the IDM. Some think it's when your oil gets too low causing the head to get too hot and cook the wiring.).

I have a draft writeup on mine here, will cover waterproofing the IDM asap. Don't laugh.. I'm still getting the formatting of the site set up how I want it, but the pictures of the harness may help you.

Note: Autozone will rent you a basic code reader, but it WILL NOT read the advanced codes for diesel and run a buzz test. I bought an AutoEnginuity® scan tool and it did the job.

[mnmnm]

yeah, we went uvch and drivers bank was almost off, it didnt lok bad, so we put it back together and retrofitted a rubber tube under the catch latch to ensure it didnt happen again. Problems were the same. Started testing the ipr resistance, gave the batteries an overnight charge, and just now, I have no flashing lights and it fired right off. Its been idleing about 10 min now. No idea what we have done to fix it, but needless to say I dont trust we fixed anything just by reading resistance on the ipr. would bad batteries make those wts and wif lights flash like that? also, now that its running, the alternator is outputtin 14.6 volts

[airbassador]

Was it raining, or just misting when your issues started? Maybe it just dried out?

Mine can start dying on me, even on startup and if I park it for a day and let it dry out it runs fine. I've read that folks have pulled the IDModule out from the fenderwell to find it sloshing with water. I just haven't had time to check mine yet.

[mnmnm]

Yeah, we pulled the idm out already. Its dry and functional as we tested a known workin one also. The truck is now dead again. It will crank over, but will not start. The flashing lights are once again on and we are at a loss.

[NCHornet]

The flashing lights are strange, could be a PCM problem, are you sure you are getting fuel while cranking? How do you know? Have you scanned for codes?

NCH

[tubular031]

I am thinking the same thing as NCH. sounds like a PCM issue.

[mnmnm]

After ALL of you have kept my flame burning for at least 300k miles, without scan tools, I assume you are right. The "mobile" diesel mechanic is comin over now with all the scanning equip. He said he WILL tell me whats wrong with it for $130. I will post the results of his findings, and thanks a bunch for tryin and all the post that kept me rollin so far.

[mnmnm]

My problem is solved, Come to find out, there was a superchips piggyback chip plugged into my computer that shorted out causing computer to not comunicate. Removed computer and the chip kinda fell on the ground. plugged the computer back up and everything is back to normal... Now I guess Ill be gettin a programmer. Thanks everyone. yall did nail it with the pcm issue.