-) Back leak Test (Static). ) Remove the engine cover and intercooler. 2) Remove the back leak hose from each injector (4EA). Back leak tester. 3) Install the visible hoses of the back leak tester to the injector fuel return hole (4EA) as shown in the pictures.
-) Back leak Test (Static). 4) Disconnect the common injector connector. - The ECM cannot operate the injectors. 5) Disconnect the IMV(Inlet Metering Valve) connector from the high pressure pump side. - High pressure pump operates with maximum pressure while the is engine cranking. High pressure gauge set. -When you want to check the high pressure, turn on the power switch after connecting the line to the battery and rail pressure regulating valve To battery To rail pressure sensor 6) Connect the high pressure gauge set to the battery and rail pressure sensor after disconnecting the rail pressure sensor connector.
-) Back leak Test (Static). 7) Crank the engine for 5 ~ 6 seconds. - Read the maximum pressure on the high pressure gauge set while cranking. Normal pressure : Above 050 bars. - Measure the length of the back leaked fuel in each visible hose. (See pictures). - Measure and compare each back leaked fuel amount in the visible hoses. - Make sure to conduct a back leak test at least twice Back leaked fuel length Result of High pressure pump & Injector back leak test. Case High pressure Injector back leak length Result 050 ~ 500 bars 0 ~ 20 cm Normal (HP pump & Injector) 2 0 ~ 050 bars 0 ~ 20 cm HP pump abnormal 3 200 ~ 050 bars 20 ~ 50 cm Injector abnormal 4 Out of range 0 ~ 20 cm Common rail sensor & tester abnormal Notice : Do not replace all injectors simultaneously.
-2) Hi pressure pump test (Capacity) ) Remove the fuel injector pipes (4 EA) between the common rail and injector. - The injector hole should be covered by a dust cap. SST for high pressure pump test Pressure regulator. 2 2 Dust cap. 3 3 Plug. 2) Install the pressure regulator (EA) and plugs (3EA) from the CRDi SST set. 3) Connect the high pressure gauge set to the battery and rail pressure sensor after disconnecting the rail pressure sensor connector.
-2) Hi pressure pump test (Capacity) 4) Disconnect the IMV connector from the high pressure pump side. - Press the hand priming pump several times. Priming pump 5) Crank the engine for 5~6 seconds. 6) Measure the fuel pressure with a high pressure gauge set while cranking the engine - Make sure to conduct the high pressure pump test at least twice. Result of High pressure pump test. Case High pressure Result Remark 050 ~ 500 bars Normal (High pressure pump) 2 0 ~ 050 bars High pressure pump abnormal Check the low pressure line 3 Out of range Common rail sensor abnormal Check the rail sensor & tester Sensor abnormal Low Pressure Normal Note : Before replacing the High pressure pump, check the metal chip in the fuel filter first. If metal chips are found in the fuel filter, flush the fuel line, inclusive of the fuel tank, and replace the parts as needed.
-3) Low pressure line test Low pressure line tester (Vacuum). - Be sure to use a vaccum gauge because the fuel feeding pump is inside the HP pump. ) Disconnect the fuel hose between the outlet port of the fuel filter and the inlet port fuel hose of the high pressure pump. Fuel filter Hi pressure pump 2) Install a low pressure gauge between the fuel filter outlet port and the high pressure pump inlet port. 3) Remove the air in the low fuel line by using a hand priming pump.
-3) Low pressure line test 4) Check air infiltration while cranking the engine. If you can see excessive air bubbles in the fuel line, then check the fuel line from the fuel tank to filter outlet port. 5) Check for low pressures at the low pressure line while cranking the engine. Result of Low pressure line test. Case Vacuum Result Remark 8 ~ 9 cmhg System normal 2 20 ~ 60 cmhg Filter or Fuel line clogging 3 0 ~ 7 cmhg Air leak in the system / Suction pump Damage
-4) Flushing procedure for injection pipe and common rail Make sure to clean the injection pipes and common rail before assembling. Fuel pipe end Air gun nozzle ) Make sure to clean the injection pipes by using air gun. Cleaning by air gun 2) Temporarily tighten the injection pipes using hand to the common rail side and injector side as shown in the picture. Temporarity tighten the injection pipes 3) Disconnect the IMV connector from the IMV on the high pressure pump. 4) Crank the engine 2~3 times for 5~6 seconds. 5) Remove all test components and assemble the injection pipes to the common rail and injectors 6) Install the IMV connector to the IMV in the high pressure pump. 7) Tighten the all injection pipes. 8) Make sure to clean the leaked fuel. 9) Check for fuel leakage in the fuel system after starting the engine.
2. Engine possible to start. 2-) Back leak Test (dynamic). ) Remove the engine cover and intercooler. 2) Remove the back leak hose from each injector (4EA). 3) Install the visible hoses of the back leak tester to the injector fuel return hole (4EA) as shown in the pictures. 4) Run the engine and keep it at idle for 3 min., then raise the engine rpm to 2500 rpm, and keep at 2500 rpm for 2 minutes. After 2 minutes, stop the engine. 5) Measure the amount of fuel leakage. - Measure and compare the volume of the back leaked fuel from each bottle. - If the measured volume is above 25ml, replace the injector. - Perform the back leak test again with the newly replaced injector.
2. Parts Required. Condition Part Name Part Number Damaged injector only GQ00/HP00: 33800-4X500. GQ02: 3380-4X500 HP02: 3380-4X800 CT/PU: 3380-4X900 GQ: (Europe) 0K52A 3480A HP: (Europe) 3390H952 HP: (India & S. Ameri) 3390H970 HP: (India & S. Ameri) 3392H970 GQ00/HP00: 3300-4X500 GQ02/HP02/CT/PU: 3300-4X700 Qty Remark Includes gasket For India & South American, Delphi recommends the use of a sedimentor. Damaged high pressure pump GQ00/HP00: 3500-4X500 GQ02/HP02/CT/PU: 3500-4X700 GQ: (Europe) 0K52A 3480A HP: (Europe) 3390H952 HP: (India & S. Ameri) 3390H970 HP: (India & S. Ameri) 3392H970 For India & South American, Delphi recommends the use of a sedimentor.