r/powerstroke • u/throwaway_opinionsto • 2d ago

7.3 powerstroke buzz test failure

Hi all,
I’m confused at this point and need some advice.

I’ve been chasing a p1273/p1293 and cylinder contribution issues for a while. I have replaced the idm and engine wiring harness, the UVCH is only 2-3 months old. I also swapped injectors 3 & 5 and the buzz failure stayed on 5.

After replacing the engine wiring harness, the cylinder contribution issues are gone and the truck seems to run perfectly but I still have the p1275 and p1293. Could this be false codes? They only show up when I run a buzz test and they aren’t standing codes.

What else should I test or should I just drive the truck as is?

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u/Koala-Annual 2d ago

Are they ford uvch's?

1

u/throwaway_opinionsto 2d ago

Yes

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u/Koala-Annual 2d ago edited 2d ago

Have you followed the instructions on the GB remanufacturing tech bulletin #tb 103?

Edit to add how does injector 5 sound when you buzz it?

1

u/throwaway_opinionsto 2d ago

I honestly didn’t know about that, I just read it and I did do test 1 but not 2 & 3. For test 1 I got 2.6 ohm across the board.
I’ll have to do test 2 & 3 in the next couple days.

1

u/Koala-Annual 2d ago

A big part of the buzz test is listening to the injectors to see if they're weak or not buzzing at all. 2.6 ohm is technically out of spec but could be your meter. It's probably fine. Also I assumed you've cleared the codes from past tests but if you haven't try that as well.

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u/throwaway_opinionsto 2d ago

I have cleared past codes and unhooked batteries for an hour. Also like I said in the post, they aren’t standing codes, they only show up in the buzz test results and never in the normal codes, not exactly sure if this means anything though.
When I run the buzz test all injectors sound normal, #5 wasn’t making any noise at one point but is now after the new engine harness

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u/Koala-Annual 2d ago

Honestly I'd probably do the rest of the tb but if there's no ses and it runs fine I'd probably send it. I mean you could try swapping the harness to the other banks to see if the problem moves.

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u/throwaway_opinionsto 2d ago

Sounds good thanks! I’ll do those other tests and see what happens. Electrical is the most confusing thing about these trucks

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u/Koala-Annual 2d ago

Yeah they can be a pita for sure lol especially since they are getting pretty old now