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Diagnostic Test

WARNING: This page is about a different car, the 2016 Dodge Journey and 2015 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK FOR AN ACTIVE DTC 
    1. Diagnose and repair any other active component or circuit DTCs before continuing with this procedure.
    2. Turn the ignition on.
    3. With the scan tool, read DTCs. Copy DTC and Freeze Frame information.
    4. With the scan tool, erase DTCs.
    5. Operate the vehicle under conditions similar to which the DTC was set.
    6. With the scan tool, view the Misfire Monitor to see which cylinders are effected.
      NOTE:

      It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set or to show misfires on a particular cylinder.

      Are there excessive misfires shown or is the DTC pending at this time?

      Yes 

      • Go To  2

      No 

  2. VISUAL INSPECTION 
    NOTE:

    Anything that affects the speed of the crankshaft can cause a misfire DTC.

    NOTE:

    When a Misfire is detected for a particular cylinder, the PCM will shut down that cylinder's Injector Control circuit.

    NOTE:

    Misfires detected during a deceleration are indicators of mechanical concerns.

    1. Visually inspect the engine for any of the following conditions:
      • Worn serpentine belt. Refer to INSPECTION .
      • Binding Engine-Driven accessories: A/C Compressor, P/S Pump, Water pump.
      • Misalignment of the Water pump, P/S Pump and A/C Compressor pulleys.
      • Corroded PCM power and ground circuits.
      • Improper CKP, CMP, MAP and TPS mounting.
      • Poor connector/terminal to component connection for CKP Sensor, CMP Sensor, MAP Sensor, TPS, Fuel Injector, Ignition Coil, etc.
      • Vacuum leaks.
      • Restricted Exhaust system. Perform the CHECKING EXHAUST RESTRICTION diagnostic procedure. Refer to RESTRICTION CHECK .
      • Restricted Air Induction system.
      • Internal engine component failures.
      • Overfilled engine oil or transmission.
      • Extremely out of balance tires or warped brake rotors.

      Were any of the above conditions present?

      Yes 

      No 

      • Go To  3
  3. CHECK FOR A FUEL OR IGNITION SYSTEM PROBLEM 
    1. Start the engine and allow it to idle long enough for the O2 Sensor to warm up and go into closed loop operation. This may take a couple of minutes.
    2. With the scan tool, observe the voltage reading of the Downstream O2 Sensor for the bank on which the misfire was present.
      NOTE:

      If the misfire is caused by a lack of fuel condition, the O2 Sensor voltage will tend to stay at the low end of the range (approximately 2.5 volts). If the misfire is caused by a lack of or poor quality spark condition, the O2 Sensor voltage will tend to stay at the high end of the voltage range (approximately 3.5 volts).

      Does the Downstream O2 Sensor voltage reading tend to be staying at the low end (2.5 volts) or high end (3.5 volts) of the voltage range.

      High end of the range (3.5 volts) 

      • Go To  4

      Low end of the range (2.5 volts) 

      • Go To  7.
  4. IGNITION SYSTEM OPERATION 
    WARNING:

    When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

    1. Turn the ignition off.
    2. Remove the Ignition Coils. Refer to COIL, IGNITION, REMOVAL .
    3. Connect the Ignition Coil harness connectors.
    4. Disconnect the Fuel Injector harness connector of the cylinder being tested.
    5. Install a spark tester on the Ignition Coil.
    6. While cranking the engine observe the spark coming from the spark tester.
      NOTE:

      Check all of the cylinders that were showing a misfire.

      NOTE:

      A crisp blue spark that is able to jump the gap of the spark tester should be generated at the coil on plug and at the end of the ignition wire.

      Is good spark present on all cylinders?

      Yes 

      • Go To  5

      No 

      • Go To  11
        NOTE:

        Connect the Fuel Injector harness connector before continuing.

  5. INSPECT THE SPARK PLUG 
    1. Turn the ignition off.
    2. Remove the Spark Plug(s) in accordance with the Service Information. Refer to SPARK PLUG, REMOVAL .
    3. Inspect the Spark Plug(s) for the following conditions:
      • Cracks
      • Carbon Tracking
      • Foreign Material
      • Gap size out of specifications
      • Loose or broken electrode
      NOTE:

      Lightly tap the bottom of the spark plug on a solid surface. The electrode in the spark plug should not move.

      Were any of the above conditions present?

      Yes 

      No 

      • Go To  6
  6. SPARK PLUG 
    1. Turn the ignition off.
    2. Exchange the Spark Plug with a known good cylinder that was not indicating a misfire.
    3. Start the engine and monitor the misfire monitor screen.

      Did the misfire switch to the previously good cylinder?

      Yes 

      No 

      • Go To  10
  7. FUEL PRESSURE CHECK 
    1. Perform the CHECKING THE FUEL DELIVERY SYSTEM test procedure. Refer to CHECKING THE FUEL DELIVERY SYSTEM (HARD START) .
      NOTE:

      Fuel pressure specification is 400 kPa +/- 14 kPa (58 psi +/- 2 psi).

      Were any problems found with the fuel system?

      Yes 

      No 

      • Go To  8
  8. FUEL INJECTOR CONTROL 
    1. Turn the ignition off.
    2. Disconnect the Fuel Injector harness connector of the misfiring cylinder.
    3. Turn the ignition on.
      NOTE:

      When a Misfire is detected for a particular cylinder, the PCM will shut down that cylinder's Injector Control circuit.

    4. Install an Injector Noid light.
    5. With the scan tool, actuate the Fuel Injector.

      Does the Noid light blink/flicker during the actuation?

      Yes 

      • Verify that there is good pin to terminal contact in the related Injector and the Powertrain Control Module connectors. Replace the Fuel Injector. Refer to INJECTOR(S), FUEL, REMOVAL .
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .

      No 

      • Go To  9
  9. INJECTOR CONTROL CIRCUIT 
    1. Turn the ignition off.
    2. Remove the Injector Noid light.
    3. Disconnect the PCM C2 harness connector.
    4. Check the Injector Control circuit for an open, short to ground and short to voltage.

      Was a problem found with the Injector Control circuit?

      Yes 

      • Repair the excessive resistance or short in the Injector Control circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .

      No 

      • Go To  15
  10. ENGINE MECHANICAL 
    1. Check for any of the following conditions/mechanical problems:
      • ENGINE VACUUM - must be at least 13 inches in neutral
      • ENGINE VALVE TIMING - must be within specifications
      • ENGINE COMPRESSION - must be within specifications
      • CYLINDER LEAKAGE TEST - must be within specifications
      • ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks
      • ENGINE PCV SYSTEM - must flow freely
      • TORQUE CONVERTER STALL SPEED - must be within specifications
      • POWER BRAKE BOOSTER - no internal vacuum leaks
      • FUEL - must be free of contamination
      • VALVE SPRINGS - cannot be weak or broken
      • CAM LOBES - must not be worn excessively
      • CAM SHAFTS - must not be worn or have excessive endplay

      Are there any engine mechanical problems?

      Yes 

      No 

      • Go To  15
  11. CHECK THE ASD RELAY OUTPUT CIRCUIT 
    NOTE:

    The following test steps will apply to the suspect cylinder from step 4.

    1. Turn the ignition off.
    2. Disconnect the Coil on Plug harness connector.
    3. Turn the ignition on.
    4. With a scan tool, actuate the ASD Relay.
    5. Using a 12-volt test light connected to ground, probe the ASD Relay Output circuit in the Coil on Plug harness connector.

      Does the test light illuminate brightly?

      Yes 

      • Go To  12

      No 

      • Repair the open or short to ground in the ASD Relay Output circuit between the PDC and Coil on Plug harness connector.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
        • NOTE:

        Stop All Actuations.

  12. IGNITION COIL 
    WARNING:

    When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

    1. Using a 12-volt test light connected to a 12 volt source, probe the Coil Control circuit at the Coil on Plug harness connector.
    2. Crank the engine for 5.0 seconds while observing the test light.

      What is the condition of the test light while cranking the engine?

      Brightly blinking. 

      • Replace the Ignition Coil in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .

      ON constantly. 

      • Go To  13

      OFF constantly. 

      • Go To  14
  13. CHECK THE COIL CONTROL CIRCUIT FOR A SHORT TO GROUND 
    1. Turn the ignition off.
    2. Disconnect the PCM C2 harness connector.
    3. Measure the resistance between ground and the Coil Control circuit in the Coil on Plug harness connector.

      Is the resistance above 10k Ohms?

      Yes 

      • Go To  15

      No 

      • Repair the Coil Control circuit for a short to ground.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  14. CHECK THE COIL CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    1. Turn the ignition off.
    2. Disconnect the PCM C2 harness connector.
    3. Measure the resistance of the Coil Control circuit between the Coil on Plug harness connector and the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  15

      No 

      • Repair the Coil Control circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  15. POWERTRAIN CONTROL MODULE (PCM) 
    1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Ignition Coil and the Powertrain Control Module (PCM).
    2. Look for any chafed, pierced, pinched, or partially broken wires.
    3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Ignition Coil and the Powertrain Control Module connectors.
    4. Refer to any Service Bulletins that may apply.

      Were there any problems found?

      Yes 

      No 

      • Replace and program the Powertrain Control Module in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
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