How does a fuel rail pressure relief valve work?
The pressure regulation valve serves with the quantity control valve to control the common rail pressure. The pressure relief valve simply allows more or less high pressure fuel to flow into the back leak system thus increasing or decreasing the fuel pressure in the rail. Excess fuel returns to the fuel tank.
What’s the low fuel pressure code on a Duramax?
Duramax LBZ and LMM P0087 Low Fuel Pressure code Summer comes, temps rise, and the working trucks with relatively high miles start to set a P0087 code and go into limp mode while towing. I am on the receiving end of continuous calls over the past few years inquiring what to do.
What should the rail pressure be on a Duramax LBZ?
The dealer can use his Tech 2 scan tool to control the injection pump and increase desired rail pressure to max of 160mpa at idle. The observed actual pressure should follow desired or at least be quite close. If not then step 3 is necessary to eliminate the rail pressure relief valve as a possible leak. Step three: Bottle test.
What happens when a fuel pressure relief valve weakens?
After some time, the valve weakens and may drop fuel pressure when it’s not needed and cause a host of problems. A weak valve can trigger engine codes P0087 or P1093. It may also be responsible for excessive smoke, poor driveability, poor mileage and a loss of power.
Is the fprv on a Duramax 01-04?
Rating is available when the video has been rented. This feature is not available right now. Please try again later. Watch how we test a faulty fprv on an 01-04 LB7 Duramax. Symptoms were hard/no start, long crank time, white smoke. Very little loss of power noticed. Truck has FASS pump no other upgrades Loading…
Duramax LBZ and LMM P0087 Low Fuel Pressure code Summer comes, temps rise, and the working trucks with relatively high miles start to set a P0087 code and go into limp mode while towing. I am on the receiving end of continuous calls over the past few years inquiring what to do.
The dealer can use his Tech 2 scan tool to control the injection pump and increase desired rail pressure to max of 160mpa at idle. The observed actual pressure should follow desired or at least be quite close. If not then step 3 is necessary to eliminate the rail pressure relief valve as a possible leak. Step three: Bottle test.
Why does the fuel pressure relief valve drop?
The valve dissipates fuel pressure to prevent overloading the fuel system. After some time, the valve weakens and may drop fuel pressure when it’s not needed and cause a host of problems. A weak valve can trigger engine codes P0087 or P1093.
When does a Duramax LBZ go into limp mode?
Summer comes, temps rise, and the working trucks with relatively high miles start to set a P0087 code and go into limp mode while towing. I am on the receiving end of continuous calls over the past few years inquiring what to do. This has prompted me to write this Tech Tip to help explain better what we are finding.