FAQ
Q:What does a fuel pressure control valve do?
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.
Q:What causes low fuel rail pressure?
Typical causes for low fuel pressure include a dirty fuel filter, weak pump, incorrect tank venting, restricted fuel lines, a clogged pump inlet strainer and faulty electrical control.