I bought a 2000 F250 7.3 with 129K. One owner, perfect condition. Only problem was that it didn't run. Got it home, cranked and cranked and it finally ran. Just had air in the oil system. Ran really well until I powerwashed the top and underside of the truck to get a bunch of gunk off it. Right after pulling out of the wash station, the truck began to run like garbage. To the floor I was only doing 15-20 mph and blowing white smoke. Had to pull over several times on the 3 mile drive back home. Did some research and learned about the wiring harnesses that connect to the valve covers and the UVCWH. Disconnected all of that and put high pressure air to it. All dry. Still had the issue. Checked all connections on the UVCWH, those were good. So I went to the injectors, when idling it sounded like it was missing. I unplugged injector 1 and nothing changed. I unplugged injector 2 and it sounded even worse. So I thought, must be an injector but I couldn't confirm as no local shop can test an injector out of truck. I bought the AE scanner and I did a buzz test. All 8 injectors buzz but cylinder 1 failed I decided to unplug cylinder 3 and plug injector 1 into the cylinder 3 injector plug but cylinder 3 didn't fail so the injector is good?? I unplugged the UVCWH for cylinder 1, 3, 5, 7 and did another buzz test. I heard 8 buzzes but cylinder 1 fails. WTF?? I started thinking IDM so I unplugged that, cleaned it all out and put it back. Run another buzz test and cylinder 1 and 3 fail now. My brain had enough confusion for the day so I called it quits. What the heck is going on with this thing?? I know it's something electrical and I know the UVCWH is working properly and that the injectors are fine. I really don't want to waste $250 on a reman IDM only to find out it wasn't the issue. Anyone ever experienced electrical gremlins on a 7.3L?

 

How did the injectors sound during the buzz test? Any of them sound muffled or different than the others?

 

Yes! Half of them sounded good and the other half seemed much quieter and muffled. Sounds like you might have an idea? I hope. Haha

 

can you take a video with your phone or laptop?

Which half were muffle? Odd or even?

You can test the 42 pin connector with a multimeter Since it just happened after the power wash I would suspect the electrical connection first. I'll post up the test steps.

 

I'll run a buzz test tomorrow and post it up. Thanks for the quick response!

 

No problem & welcome to FTE.........

Basically you need to:

Using AE:

Check for trouble codes & write them down
Clear out the trouble codes
Run a KOEO test and recheck for codes
Injector buzz test - see if any sound different from the rest.

depending on the codes you might need to ohm test the injectors through the 42 pin connector on the drivers side valve cover.

 

Here's a couple of links and a pic that should help.

 

After pulling my hair out and going crazy over the issues, I called a buddy of mine who is former ford diesel mechanic. Turns out it was the EBP sensor. A $100 part and now the truck runs like a dream. But, the former owner put a crap Chinese turbo on it since he didn't feel like spending the money on the right one. Now the turbo fan is rubbing against the inside of the compressor housing. Goodie.

 

The power wash likely did your EBP sensor in. There is a rule to never power wash the top side. Too many sensors don't like this, and the electrical connectors are not engineered to endure a high-pressure soaking - that's a different connector spec.

Simple Green and a soft rinse is the standard practice.

 

Good to know for the future. I don't plan on doing that again...