Circuit/System Testing
WARNING: This page is about a different variant/trim than selected.
Fuel Pressure Low
- Verify none of the conditions listed below exist:
- Restricted fuel feed pipe
- Restricted or plugged strainer
- Poor connections at the fuel pump harness connector and the ground circuits
- If a condition exist
Repair as necessary.
- Go to next step: If a condition does not exist
- Test or replace the G12 Fuel Pump.
Fuel Pressure High
- Verify none of the conditions listed below exist:
- Air in fuel feed Pipe
- Excess vapor in fuel feed pipe
- If a condition exist
Repair as necessary.
- Go to next step: If a condition does not exist
- Test or replace the G12 Fuel Pump.
Fuel Pressure Leaks Down
- Ignition OFF, relieve the fuel pressure. Refer to Fuel Pressure Relief .
- Install the J 37287 Fuel Line Shut-Off Adapters between the fuel feed pipe and the fuel rail.
- Open the valve on the J 37287 Fuel Line Shut-Off Adapters.
- Ignition ON, command the Fuel Pump Enable On with a scan tool.
- Close the valve on the J 37287 Fuel Line Shut-Off Adapters.
- Verify the scan tool Fuel Pressure Sensor parameter does not decrease greater than 34 kPa (5 PSI) in 1 min.
- If the fuel pressure drops
Test or replace the G12 Fuel Pump.
- Go to next step: If the fuel pressure does not drop
- If the fuel pressure drops
- Locate and replace the leaking Q17 Fuel Injector.
Fuel Pressure Drops OFF
- Verify none of the conditions listed below exist:
- Restricted fuel feed pipe
- Restricted or plugged strainer
- Poor connections at the Fuel Pump harness connector and the ground circuit
- If a condition exist
Repair as necessary.
- Go to next step: If a condition does not exist
- Test or replace the G12 Fuel Pump.