High rail pressure

[cumminsman202]

Ok I just rebuilt my trans got the truck up and running when I first started it sounded like it was miss foraging real bad ran the codes glow plug module replaced that wasn't missing firing as bad now my rail pressure is at 12k to 13k at idle idk what the problem is no codes are coming up I'm lost the mods on the truck are 100% injectors dual cp3s 475 over 68 any help would be appreciated thanks

 

[cumminsman202]

And if my rail pressure gauge is unhooked it acts all dumb an stuff like the fuel pump coming on on the first click of the key an not the second an will not turn over at all I'm thinking either the fpr or rail pressure sencor

 

[Ne-max]

What's your lift pumps pressure at?

 

[cumminsman202]

Not for sure how would I test it and what's it suspost to be?

 

[Chevy1925]

Holy hell man. Sentence structure is your friend. Trying to figure this out with an already fried brain from work ain't going well.

 

[cumminsman202]

Holy hell man. Sentence structure is your friend. Trying to figure this out with an already fried brain from work ain't going well.

Ain't got no time for periods lol

 

[Chevy1925]

Ain't got no time for periods lol

Then best of luck to ya.

 

[ikeG]

Is it a misfire or just noisy injectors from the high rail pressure? Too high of lift pump pressure will make it idle @ too high rail pressure.

 

[cumminsman202]

Yea it was a real bad knock at first. Then I ran the codes an it said glow plug module so changed it an it stopped, an now it Idles fine but rail pressure is 13k. When it's in gear it drops to maybe 11k. What would make the fuel pump all of a sudden higher the pressure?

 

[Ne-max]

If you could answer questions we could help. Good luck:thumb:

 

[cumminsman202]

If you could answer questions we could help. Good luck:thumb:

I'm gonna test the fuel pressure tomorrow an see what it is.

 

[cumminsman202]

Tested fuel pressure it’s at 9 psi an I replaced the fpr on the main cp3 also when I unplug my fuel rail pressure gauge it will die if it unplug from the harness or if I unplug it from the gauge... kinda weird...... but I read the fuel rail pressure on my code reader an it says it bounces around from 6300 to 7000. I’m guess it may have something to do with my wiring because I’m throwing a P0880 code also (tcm power input signal) and I just replace the trans... anybody else ever have this happen?