Can a fuel rail high pressure relief valve go bad?

Can a fuel rail high pressure relief valve go bad?

These valves are known to go bad and open prematurely causing a “fuel rail PSI low” problem. Once a valve is weakened it tends to get worse. Replacing the valve with a new one is much safer than shimming it and taking your chances with the high (22,000+ PSI) pressures that this valve was designed to protect from.

Where is the common rail high pressure relief valve?

Common Rail High Pressure Relief Valve This is the pressure relief valve located in the driver’s side fuel rail on the 2004.5 – 2007 Duramax LLY & LBZ engines. These valves are known to go bad and open prematurely causing a “fuel rail PSI low” problem. Once a valve is weakened it tends to get worse.

Where is the pressure relief valve on a Duramax LBZ?

This is the pressure relief valve located in the driver’s side fuel rail on the 2004.5 – 2007 Duramax LLY & LBZ engines. These valves are known to go bad and open prematurely causing a “fuel rail PSI low” problem. Once a valve is weakened it tends to get worse.

What should fuel rail pressure be at idle?

With the engine idling or at an idle, command the fuel pressure control to 180 MPa (23,206 psi) with a scan tool. Observe the Actual Fuel Rail Pressure parameter. The actual fuel pressure should be the same as the commanded pressure.

Where is the pressure relief valve on a Duramax engine?

Included on the fuel rail is a pressure relief valve which is a spring-loaded valve on the back side of the fuel rail. The valve’s job is to release pressure in the event that it becomes too high. When pressures surpass the allotted threshold, the spring compresses, releasing rail pressure.

What to do if fuel rail pressure is less than desired?

Fuel pressures should be the same for both parameters. ⇒ If the Actual Fuel Rail Pressure is less than the Desired Fuel Rail Pressure, refer to Fuel System Diagnosis – High Pressure Side . ⇒ If fuel system tests normal, refer to Diagnostic Aids.

Is there a problem with my Duramax fuel rail?

Never a single problem with it until lately. The first time I hammer on it for the day, fuel rail pressure jumps to 26,000 for about 2-3 seconds, but then falls off to 10,000 and won’t come back up. But (here’s the weird part) after it does that once, it works normally thereafter.

What is the fuel rail number on Bosch pressure limiting valve?

The valve is a Bosch part at ~£150. Note the fuel rail number eg xxx-RGB-xxxxx. A common number on the part found on the old and new valve was F166. On the part receipt it was called a “pressure limiting valve” p/n F00R001166. Use this information at your own risk.