How much fuel pressure should a LB7 have?
By Sophia Dalton
How much fuel pressure should a LB7 have?
The example below shows a 2002 LB7 engine cranking over with the ignition relay unplugged. Note that the fuel rail pressure is at 24,053 psi. As stated previously, the fuel pressure with the Ignition relay unplugged needs to be a minimum of 2500 to 3500 psi during cranking for the return rate test results to be valid.
What should LB7 fuel rail pressure be at idle?
As it gets warmer it will drop. At 185 it should be about 4.3kpsi. It might go up or down 100 psi, that’s normal.
How long does it take to change fuel pressure regulator on LB7?
This guide will demonstrate the procedures to install the LBZ/LLY fuel pressure regulator in the LB7 duramax. The time taken to accomplish this was around 1.5 to 2 hours.
What should lb7 injector balance rates be?
GM states that balance rates should be no more than plus or minus 4 (+4/-4) in park at operating temperature. Unfortunately balance rates do not always provide a 100% accurate diagnosis of the injector’s performance due to numerous variables present in the engine.
Where is the FPRV on a Duramax?
This valve often referred to as FPRV is located in the rear of the driver’s side fuel rail on the LLY, LBZ, and LMM, and is buried in the valley on the LB7 and functions much like the Temp and Pressure valve on your water heater.
How long does it take to install the LBZ/LLY fuel pressure regulator?
Enter your ride HERE to be a part of this months Ride of the Month Challenge! This guide will demonstrate the procedures to install the LBZ/LLY fuel pressure regulator in the LB7 duramax. The time taken to accomplish this was around 1.5 to 2 hours.
How does the LBZ FPR work?
The Design of the LBZ FPR allows you to push higher fuel pressure through your truck because the LBZ FPR has more points to monitor pressure. It can provide a more accurate reading than the prior versions could.
Should I replace the FPR on my LB7?
Just replaced the FPR on my LB7 although I went stock FPR rather than LBZ FPR. It absolutely cured the lope idle and surges and P0089 occasional codes. My truck has 236k miles. While for the most part this write up was accurate, the EGR version of the LB7 does yield some challenges although quite doable.
