Circuit/System Testing
WARNING: This page is about a different variant/trim than selected.
- Ignition/Vehicle - Off
- Verify the condition does not exist : Fuel System - Leaking
- If the condition exists
Refer to : Fuel Leak Diagnosis
- Go to next step : If no condition exists
- If the condition exists
- Engine - Idling
- Verify the scan tool parameter : Fuel Pressure Sensor = 370 to 450 kPa (54 to 65 PSI)
- If less than 370 kPa (54 PSI)
Refer to : Fuel System Diagnosis
- If greater than 450 kPa (65 PSI)
Refer to : Fuel Return System Diagnosis
- Go to next step : If between 370 and 450 kPa (54 and 65 PSI)
- If less than 370 kPa (54 PSI)
- Perform the following procedure/test : Fuel Injector Balance Test
Verify the procedure/test passes.
- If the procedure/test does not pass
Replace the component that failed the test : Q17 Fuel Injector
- Go to next step : If the procedure/test passes
- If the procedure/test does not pass
- Perform the scan tool control function : Fuel Pressure Control - Regulator 1 - Increase & Decrease
Verify the scan tool parameter : Fuel Rail Pressure Sensor 1 = The value should change with each command.
- If the value does not change
Replace the component : Q18A Fuel Pressure Regulator 1
- Go to next step : If the value changes
- If the value does not change
- Perform the scan tool control function : Fuel Pressure Control - Regulator 2 - Increase & Decrease
Verify the scan tool parameter : Fuel Rail Pressure Sensor 1 = The value should change with each command.
- If the value does not change
Replace the component : Q18B Fuel Pressure Regulator 2
- Go to next step : If the value changes
- If the value does not change
- Test or replace the component : G18 High Pressure Fuel Pump