Fuel rail pressure help

[sideactiondiesel]

a lot of it seems to be in the tune and a possible false reading, switched to a ******* tune with a slightly higher pw 2.29 and it held 22-23k. After swapping injectors/hpfp/fuel tank/lines/fuel cooler there was no change. Ended up getting another pcm and reflashed it to stock and got completely new tunes essentially starting over on the truck, electronics wise. With the new tunes and pcm and back to our original tuner the truck will only show its holding 19k but with a desired 24k , the truck holds 19k with very little fluctuation on scan tool vs the 2k fluctuation it had before. Have not confirmed this frp on another scan tool or cts2 but the truck is a "monster" (used very loosely) for what is done to it after the pcm switch and reflash.


So basically I feel like it was something in the original pcm along with receiving a false reading, our pressure holds steady (only showing 19k) but the truck is much much quicker then it was previously.


Not sure if that helps or not but the loss of power all seems to be in connection to the original pcm that was in the truck, because after the switch and running an employees cummins in "mexico" this truck will now put multiple lengths on it over what it previously would do.

Am I missing something here or has the frp sensor never been changed? If so at what time did it get changed ?

 

[78f100]

I was assuming it had been changed already when he did injectors and pump but I may be wrong.

I just finished one Friday that had a bad frp sensor. After a hour or so of runing it would get a really choppe idle and frp would go all over the place from 5.2 to 1.8k. This was after all new turbos and up pipes, customer forgot to mention the idle issue, and I couldn't run it when it came in to tell. The hp turbo came apart busted the, up pipe and melted the hydra boost lines, and brake res almost off, customer didn't know there was a problem till the drivers fender turned black...lol. I just wanted to share that I need to post pics.
Anyway glad you got it figured out.

 

[AirFishAutomotive]

I was assuming it had been changed already when he did injectors and pump but I may be wrong.

I just finished one Friday that had a bad frp sensor. After a hour or so of runing it would get a really choppe idle and frp would go all over the place from 5.2 to 1.8k. This was after all new turbos and up pipes, customer forgot to mention the idle issue, and I couldn't run it when it came in to tell. The hp turbo came apart busted the, up pipe and melted the hydra boost lines, and brake res almost off, customer didn't know there was a problem till the drivers fender turned black...lol. I just wanted to share that I need to post pics.
Anyway glad you got it figured out.

sorry dont know how to double quote LOL

this truck had a choppy idle "randomly" at times, also on the scan tool while commanding frp it would get choppy at 12 and then 17k. All of this stopped after pcm reflash and retune

it had 2 new frp sensors. that was on of the first things, have not been constantly working on the truck its been as we have time sort of deal here and there. Seems to run extremely well currently.