Diagnostic Test

WARNING: This page is about a different car, the 2020 Jeep Renegade. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DTC
1. Start the engine.
2. Allow the engine to reach normal operating temperature.
3. Test drive the vehicle in accordance with the when monitored conditions.
4. With the scan tool, read DTCs and record on the repair order.
  Is the DTC active or pending?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK FOR AN INTAKE MANIFOLD LEAK AT A SPECIFIC CYLINDER ON BANK 1
1. Check for any of the following conditions, but not limited to:
  - Intake manifold seals leaking at a specific cylinder.
  - Intake plenum leak at a specific cylinder.
  - Warped/cracked Intake Manifold or plenum.
  - Vacuum leak at a Fuel Injector O-Rings.
  Were any issues found?
  
  Yes
  - Perform the appropriate repairs.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 3
CLEAN THE VALVE TRAIN AND COMBUSTION CHAMBERS
1. Using the Mopar Combustion cleaner, de-carbon the engine.
2. After driving and clearing the combustion cleaner from the engine, erase any DTCs with the scan tool.
3. Test drive the vehicle in accordance with the when monitored conditions.
4. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Go To 4
  No
  - Cleaning the combustion chambers repaired the fault.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK FOR FUEL INJECTOR ISSUES AT A SPECIFIC CYLINDER ON BANK 1
1. Check for any of the following conditions, but not limited to:
  - Verify correct voltage supply at each Fuel Injector.
  - Verify correct control circuit operation at each Fuel Injector.
  - Verify correct Fuel Injector operation (spray pattern).
  Were any issues found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
CHECK THE CYLINDERS ON BANK 1 FOR LOW COMPRESSION AND IGNITION SYSTEM ISSUES
1. Perform a cylinder compression and/or cylinder leak down test on each cylinder on bank 1.
2. Check the ignition system for any of the following conditions, but not limited to:
  - Verify correct voltage supply at each Ignition Coil.
  - Verify correct control circuit operation at each Ignition Coil.
  - Verify that the Spark Plugs are matching and are equivalent to OEM specifications.
  - Verify correct Spark Plug gap.
  - Visually inspect the Ignition Coils and Spark Plugs for signs of carbon tracking.
  - Visually inspect the Ignition Coils for signs of damage.
  Were any issues found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 6
CHECK FOR VALVE TRAIN AND VARIABLE VALVE SYSTEM ISSUES
1. Check the valve train for any of the following conditions, but not limited to:
  - Verify correct operation of the Multi Air system.
  - Check for broken, worn or improperly installed valve springs.
  - Check for broken, worn or improperly installed Camshaft followers.
  - Check for worn Camshaft lobes.
  Were any issues found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 7
REPLACE THE UPSTREAM O2 SENSOR AND RETEST FOR DTC
1. Replace the Upstream O2 Sensor. Refer to SENSOR, OXYGEN, REMOVAL AND INSTALLATION .
2. With the scan tool, erase DTCs.
3. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
4. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Anything that can cause an air/fuel ratio imbalance in an individual cylinder will cause this DTC to set. Verify all of the items in this test and any other mechanical items that may cause this DTC to set. Also check for any Service Bulletins that may apply to this fault code.
  No
  - Replacing the Upstream O2 Sensor repaired the fault.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .