code po1277?

[77 powerstroke]

what code is this

[pinkfloyd]

Trouble Codes - Powerstroke Nation hope this helps you out

[guzzle]

P1277 - High to Low Side Open - Cylinder 7 Sounds like an injector circuit failure. Bad UVC harness or pigtail.

[SCUFFY828]

agreed , pull the passenger valve cover off and reconnect the injector harness , youll see where its loose

[J-ROCK]

I have the same code coming up and the truck is running kinda rough, has a bit of a shake even once it's warmed up.
We are having a heat wave here and it still doesn't run well until it's at normal temp. So I buzz tested the injectors yesterday and got this code.
While the buzz test was running I heard all the injectors fire, does that rule out a stuck or bad injector and pretty much narrow is down to the harness or pigtail?

[SCUFFY828]

Originally Posted by J-ROCK

I have the same code coming up and the truck is running kinda rough, has a bit of a shake even once it's warmed up.
We are having a heat wave here and it still doesn't run well until it's at normal temp. So I buzz tested the injectors yesterday and got this code.
While the buzz test was running I heard all the injectors fire, does that rule out a stuck or bad injector and pretty much narrow is down to the harness or pigtail?

pull the passenger valve cover first and look at your short harness under there , more than likely its unplugged

[Dirk]

Not running well until warm tells me it's the injector. Do a contrib/balance test and buzz test with the engine hot and see what codes comes up. Double check the harness, and check the OHM resistance of the injectors. I think the specs are 2.9-3.2 or somewhere in that range....