2005 2500 5.9 loss of rail pressure

Treerat · #1 4 Weeks Ago

Already had a new fca because of previous problem. Injectors were starting to go so I ordered ~50hp overs from Flux. Ran amazing better response, starting, and fuel mileage. After about 1000 miles I started having a problem after it got up to operating temps I would lose rail pressure and not be able to accelerate. Hard to get up to 50mph+ and boosting alot to keep it there. Fuel Mileage went down the drain. Rail pressure is normally good at idle some times drops to 3k psi. While accelerating it'll drop all the way to 1.5k psi has died 3 times while slowing down to a stop after doing 50.
Randomly it'll start running good then I have no problem all day also runs good while engine is cold

I've replaced the rail pressure sensor, rail pressure valve, Cascade overflow valve. My lift pump holds good pressure. Also had the crossover tubes re torqued. When cold if I unplug the fca it goes to around 24-35k psi warm it'll only go to 10-12k psi

MAXTORQ · #2 4 Weeks Ago

What are your lift pump pressures, and is the LP stock or aftermarket?

Treerat · #3 4 Weeks Ago

Quote:

Originally Posted by MAXTORQ

What are your lift pump pressures, and is the LP stock or aftermarket?

It's aftermarket raptor 150. Pressure was around 14psi, I adjusted it up to 25psi to see if it'd make a difference. It didn't. It seems like I'm down to an injector or crossover is bad idk. Dont want to have to pull them and send them in lol

MAXTORQ · #4 4 Weeks Ago

I doubt seriously that anything is wrong with the Soup Nazi's injectors. Flux makes nice stuff.

I would say now that you will need to find somebody with a scanner to find out what the starting pressure is and see if the rail pressure sensor and or relief valve is operating properly.

Treerat · #5 4 Weeks Ago

Soup Nazi? Lol

I was thinking maybe the installer ****ed up on the install who knows.

Starting pressure for the rail or lp?

MAXTORQ · #6 3 Weeks Ago

Yes starting rail pressure. Needs to be between 3800psi to 4700 psi. It can be a little higher but no lower.

This will tell you if you have several things going on such as rail pressure sensor, rail pressure relief bad FCA or electrical connection at FCA, and or misaligned transfer tubes.

Don't rule out a bad injector either. Even the best builder have a bad day.

Treerat · #7 3 Weeks Ago

Quote:

Originally Posted by MAXTORQ

Yes starting rail pressure. Needs to be between 3800psi to 4700 psi. It can be a little higher but no lower.

This will tell you if you have several things going on such as rail pressure sensor, rail pressure relief bad FCA or electrical connection at FCA, and or misaligned transfer tubes.

Don't rule out a bad injector either. Even the best builder have a bad day.

It ended up being loose crossover tubes. I had the shop that did the install on the injectors re torque them a second time but I guess both times they put the new guy on them and he is incompetent. Took it to another shop that could cap off the lines and see if I certain injector was causing the problem and they noticed the tubes were loose. I'm livid

MAXTORQ · #8 3 Weeks Ago

Well whatever you spent at the second shop go back to the first and see if they will reimburse the second shops labor time.