Diagnostic Test

WARNING: This page is about a different car, the 2023 Jeep Grand Wagoneer L and 2023 Jeep Grand Wagoneer. However, it is still accessible from the selected car via links, so may be relevant.

VISUALLY INSPECT THE FUEL SYSTEM FOR LEAKS OR RESTRICTIONS
1. Visually inspect the fuel system for leaks or restrictions.
  Were any fuel system issues found?
  
  Yes
  - Perform the appropriate repairs.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 2
CHECK THE FUEL PRESSURE
1. Using a lab scope, back probe the Fuel Pressure Sensor Signal circuit.
2. While observing the lab scope reading, start the engine.
  Does the Fuel Pressure Sensor Signal voltage spike above, then below the set point before settling at the set point as indicated in the monitoring conditions?
  
  Yes
  - Perform the INTERMITTENT CONDITION test procedure. Refer to INTERMITTENT CONDITION .
  No
  - Go To 3
CHECK THE FUEL PUMP OPERATION
1. Perform the CHECKING THE FUEL DELIVERY SYSTEM (HARD START) test procedure. Refer to CHECKING THE FUEL DELIVERY SYSTEM (HARD START) .
  Is the Fuel Pump Assembly operating to specifications?
  
  Yes
  - Replace the Fuel Pressure Sensor in accordance with the Service Information. Refer to FUEL PRESSURE SENSOR .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Replace the Fuel Pump Assembly in accordance with the Service Information. Refer to ASSEMBLY, FUEL PUMP, REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .