DTC codes P1271, P1272, P1277, P1273 and P1274?

Tiny
PROMIKE94
  • MEMBER
  • 1996 FORD F-350
  • 7.3L
  • V8
  • TURBO
  • 2WD
  • AUTOMATIC
  • 250,000 MILES
I just replaced the wiring harness with a different wiring harness and IDM and now I’m getting these codes when I do an injector test. The truck will not start anymore, and I also replaced the driver's side valve cover gasket before all of this. Originally, I was having an issue with the oil pressure I replaced the ipr valve and that didn’t fix it. I’m not sure what happened that now I’m getting all of these codes at once and it’s not just one side of the engine, I guess.
Sunday, September 15th, 2024 AT 6:35 PM

9 Replies

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,193 POSTS
Yep, these are wiring harness codes, is everything connected? If so, I would get another harness.

P1271 - Cylinder #1 High to Low Side Open
P1272 - Cylinder #2 High to Low Side Open
P1277 - Cylinder #7 High to Low Side Open
P1273 - Cylinder #3 High to Low Side Open
P1274 - Cylinder #4 High to Low Side Open

Let me know if you need anything else, or upload images so I can see what's going on.
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Monday, September 16th, 2024 AT 10:52 AM
Tiny
PROMIKE94
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  • 10 POSTS
So I’m not sure if this has to do with anything but my glow plug relay only has power on one big terminal and the other doesn’t. I was doing research, and it says both should have power when the key is on. I’m not sure if the wires are on correctly do you have a wire diagram for this? Thank you
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Monday, September 16th, 2024 AT 5:24 PM
Tiny
PROMIKE94
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And I put my old harness back in and I’m having the same out come with the injectors. I’m pretty sure the wires on the for from the other harness were on different so could I have burnt out this relay?
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Monday, September 16th, 2024 AT 5:26 PM
Tiny
PROMIKE94
  • MEMBER
  • 10 POSTS
GPR not for**
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Monday, September 16th, 2024 AT 6:02 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,193 POSTS
Yep, there should be power at two of the terminals for the glow plug relay, here are the wiring diagrams for the engine and glow plug relay so you can see how the system works and which wires to test.

This guide should help you as well:

https://www.2carpros.com/articles/how-to-check-wiring

Check out the images (below). Let us know what you find.
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Tuesday, September 17th, 2024 AT 8:59 AM
Tiny
PROMIKE94
  • MEMBER
  • 10 POSTS
So, I got that all sorted the test now passes but I have no fuel pressure at the valve on the fuel bowl. I’m not sure where to start from here.
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Thursday, September 19th, 2024 AT 6:58 AM
Tiny
PROMIKE94
  • MEMBER
  • 10 POSTS
Okay, I got it started. So, it starts fine then 10 seconds later the check engine light will come on and idle very rough. This was my main problem. And when I scan for DTCs nothing shows up besides when I run tests on it.
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Thursday, September 19th, 2024 AT 7:44 AM
Tiny
PROMIKE94
  • MEMBER
  • 10 POSTS
I replaced the IPR CPS and ICP sensor. When I ran the tests p1284 and p1211 pop up.
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Thursday, September 19th, 2024 AT 7:47 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,193 POSTS
Glad you could get it fixed, thanks for letting us know. Please use 2CarPros anytime we are here to help.

Sorry, we only handle one problem per thread, please post your new question here, you must be logged in.

https://www.2carpros.com/questions/new

Cheers, Ken
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Thursday, September 19th, 2024 AT 10:15 AM

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