[Powerstrokeslayer92]

Injectors have 30k on them, new 140gph lift pump with constant 15psi. When the truck is below about 160 degrees I have good rail pressure over 26k at wot and 6k at idle but when the truck gets to operating temp my rail pressure wont go above 15k and loses alot of power. No fuel in oil or visible leaks. I'm suspecting that my crossover tubes have backed out can anyone second this? Thanks

 

[GRUNT 11B]

You can easily go through and retorque your feed tubes. I have read about the PRV not working properly when it's warm, so thats something you can look into as well.

 

[Powerstrokeslayer92]

You can easily go through and retorque your feed tubes. I have read about the PRV not working properly when it's warm, so thats something you can look into as well.

Yup retorqued nuts and got good rail pressure until I popped the number 5 injector line. Since you run a prv do you see large psi spikes when you shift. If I roll into it I hold 24k and it doesn't spike but If I nail it, rp falls to about 21k then when I let off it pegs my gauge. I fried two stock prv's (from the pressure spike so I bought a plug) and I've heard of shimming them to increase pressure but do they last or do they still get weak and bleed over time. thanks

 

[cerberusiam]

Use a 6.7 PRV, won't solve the root cause but they will hold more pressure. The high pressure fuel etches the seat, that is why they leak. Really cannot stop them from popping as tha is their job, only limit the circumstances that cause the spikes.

 

[GRUNT 11B]

I don't see large spikes when i shift. You should probably find out why it's doing that and put a PRV back in.

 

[steelhead1]

26k+ RP on an '03????

?? Inaccurate gauge or RP sensor.??

May also be a worn corroded inaccurate FCA not tracking ECU commands. Replace or high end scanner and record Commanded VS Actual RP.

Your stock CP3 may not be able to supply enough fuel depending on TNT-R settings causing RP collapse on WOT then erratic buildup causing overshoot RP.

What RP setting on TNT are you running?

Most RP gauges are incapable of displaying true short duration peak pressures. If you see 26k+, it's hitting over 30k real

 

[Powerstrokeslayer92]

26k+ RP on an '03????

?? Inaccurate gauge or RP sensor.??

May also be a worn corroded inaccurate FCA not tracking ECU commands. Replace or high end scanner and record Commanded VS Actual RP.

Your stock CP3 may not be able to supply enough fuel depending on TNT-R settings causing RP collapse on WOT then erratic buildup causing overshoot RP.

What RP setting on TNT are you running?

Most RP gauges are incapable of displaying true short duration peak pressures. If you see 26k+, it's hitting over 30k real

Its the stock rp sensor, I'm running tnt-r with rail on 3 or 4. I've confirmed my gauge is accurate with a scanner but the stock sensor tops out a 26k.

 

[dsldude]

Use a 6.7 PRV, won't solve the root cause but they will hold more pressure. The high pressure fuel etches the seat, that is why they leak. Really cannot stop them from popping as tha is their job, only limit the circumstances that cause the spikes.

When you mention using the 6.7 PRV, how are you connecting the return line? The 6.7 style is not threaded for that on top.

 

[cerberusiam]

26.5k is the limit of the PRV, doesn't matter what year it is on if you unhook the FCA or change programming.

Not sure how they are doing it whether threading the PRV or putting it into the 5.9 design. Check with TC Diesel on what they have.