Circuit/System Testing
WARNING: This page is about a different variant/trim than selected.
- Ignition/Vehicle - Off
- Verify the following conditions do not exist:
- B47B Fuel Rail Pressure Sensor - Poor Connection/Skewed
- Fuel - Contaminated/Poor Quality - Refer to: Contaminants-in-Fuel Diagnosis , & Fuel System Specifications
- Fuel System - Leaking - Refer to: Fuel Leak Diagnosis
- If a condition exists
Repair or replace as necessary
- Go to next step: If no 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: Cylinder Power 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 = The value should change with each command.
- If the value does not change
Replace the component: Q18A Fuel Pressure Regulator 1 & Q18C Fuel Pressure Regulator 3
- 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 = 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
- Perform the scan tool control function: Fuel Rail Pressure - Increase & Decrease
Verify the following parameters are within 2, 000 kPa (290 PSI) of each other:
- Desired Fuel Rail Pressure
- Fuel Rail Pressure
- If not within 2, 000 kPa (290 PSI) of each other
- Go to next step: If within 2, 000 kPa (290 PSI) of each other
- Test or replace the component: G18 Fuel Pump - High Pressure
NOTE:
Fuel Rail Pressure - Maximum @ At Idle Speed = 110 MPa (15, 954 PSI)