The rail pressure-control valve sets the correct pressure in the rail as a function of engine loading, and maintains it at this level.
If the rail pressure is excessive, the pressure-control valve opens and a portion of the fuel returns from the rail to the fuel tank via a collector line.
If the rail pressure is too low, the pressure-control valve closes and seals off the high-pressure stage from the low-pressure stage.
At after run test mode or fuel cut mode, if within set time engine rpm is not dropped below the lower set value, error is detected.
The reasons are short circuit, connecting resistance, faulty rail pressure sensor, continuity of fuel pump relay, faulty rail pressure control valve, defective high pressure pump, ECM fault, etc.
Check item | Set value (Ω) |
Rail pressure control valve resistance | 2.07 ~ 2.53 Ω |
Replace the rail pressure control valve if signal voltage exceeds the set value.
Tightening torque for this replacement is 5 ± 1Nm.
Replace the faulty fuel rail assembly in case of new model vehicle within a year, or replace the faulty parts of vehicle of which model year is more than a year.
