To remove high pressure fuel system, Never perform any work engine running or within 60 minutes after the engine stops. It is recommended to wear safety glasses. Ensure the absolute cleanliness to prevent an inrush of foreign substances in high pressure fuel system.
Perform Inspect as below to check high pressure fuel system because impossible starting, engine stalls and poor power (acceleration) could be caused by abnormal high pressure fuel system.
IG KEY "OFF", ENGINE "OFF"
Install SST "CRT-1000" in the high pressure fuel system.
"CRT-1000 Tester Composition" of "Details Inspection(Equipment Setting)" reference
"CRT-1000 Tester Installation" of "Details Inspection(Equipment Setting)" reference
Inspect high pressure fuel system with engine cranking.
Specification
Common rail fuel pressure is above 1200 bar within approx. 2~3 seconds after cranking.
- If common rail fuel pressure is beyond limit pressure (approx. 1200 bar) of regulator valve (CRT-1020), Fuel is discharged through visible tube to Flask and holder (CTR-1030).
- If fuel discharged from common rail is good and Pressure of common rail is above 1200 bar, Performance of high pressure pump is normal.
Pressure of low pressure fuel system must be kept 3.5~3.8 bar at testing.
There must be no fuel leak from return hose of rail pressure regulator at testing.
When power of rail pressure regulator is "OFF" after testing, Common rail pressure is released by rail pressure regulator. (Fuel is discharged through return hose.)
Case 1 : In case that pressure of high pressure fuel system is normal.
Go to "Injector back leak inspection" procedure.
Case 2 : In case that pressure of high pressure fuel system is low.(There is fuel leak in the return nipple of the rail pressure regulator.)
Replace the rail pressure regulator (Common rail assembly) if necessary.
Case 3 : In case that pressure of high pressure fuel system is low. (There is no fuel leak in the return nipple of rail pressure regulator. Rail pressure is not above 1,200 bar or pressure rising time is too long.)
Replace the high pressure fuel pump assembly if necessary.
Case 4 : Pressure of hi pressure fuel system is abnormal or not changed.
- Specification : Rail pressure of rail pressure sensor must be 0 ~ 3.0 bar after releasing fuel pressure of common rail.
Inspect the rail pressure sensor (RPS).
