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Home >> Mercury >> 2004 >> Marauder >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Test Hd: Misfire Detection Monitor Through Pinpoint Test HY: Generator/Regulator System - CNG, Flex-Fuel & Gasoline >> Pinpoint Test HD: Misfire Detection Monitor >> Test Procedure
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Test Procedure

NOTE: Proceed to DTC testing steps listed in FAULT CODE SETTING CONDITION  table of fault code setting condition.
FAULT CODE SETTING CONDITION

Fault Code KOEO KOER Continuous Memory
P0300      HD1
P0301      HD1
P0302      HD1
P0303      HD1
P0304      HD1
P0305      HD1
P0306      HD1
P0307      HD1
P0308      HD1
P0309      HD1
P0310      HD1
P0315      HD25
P0316      HD1
P1309      HD22
  1. HD1 CHECK FOR ADAPTIVE FUEL MONITOR AND HEGO MONITOR DTCS (CONTINUOUS MEMORY) 
    • Check the PCM for self-test DTCs.

    Are DTCs P0136, P0156, P0171, P0172, P0175, P2270, P2271, P2272 or P2273 present? 

    Yes No
    GO to  HD3. GO to  HD2.
  2. HD2 CHECK FOR OTHER NON-MISFIRE CONTINUOUS MEMORY DTCS 

    Are there other non-misfire DTC in Continuous Memory present? 

    Yes No
    DISREGARD the current diagnostic trouble code (DTC) at this time. DIAGNOSE the next DTC. GO to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS . GO to  HD3.
  3. HD3 CHECK FOR ANY OTHER KOEO SELF TEST DTCS 

    Are any other KOEO DTCs present? 

    Yes No
    (If misfire or coil DTCs are present, and WDS or an equivalent tool is available, use the scope function to verify the suspect coil.).
    DISREGARD the current diagnostic trouble code (DTC) at this time. DIAGNOSE the next DTC. GO to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS .    		 Key in OFF position.
    For spark plug wires that are OK:
    GO to  HD4.
    For spark plug wires that need evaluation:
    GO to PINPOINT TEST JB step 1 .
  4. HD4 CHECK FOR ANY OTHER CODES THAT MAY CAUSE A MISFIRE 
    • Check for self-test DTCs.

    Are DTCs P1131, P1132, P1137, P1138, P1151, P1152, P1157 or P1158 present? 

    Yes No
    GO to  HD6. GO to  HD5.
  5. HD5 CHECK FOR ANY OTHER KOER DTCS 

    Are any other KOER DTCs present? 

    Yes No
    Key in OFF position. DISREGARD the current diagnostic trouble code (DTC) at this time. DIAGNOSE the next DTC. GO to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS . GO to  HD6.
  6. HD6 CHECK THE INJECTOR DRIVER PIDS INJ1F THROUGH INJ10F 
    • Key ON, engine OFF.
    • Access the appropriate INJxF PIDs for the suspect injector.

    Are the PIDs status YES? 

    Yes No
    GO to  HD7. Key in OFF position.
    For Dedicated NGV
    GO to PINPOINT TEST HA step 27 .
    For all others:
    GO to  HD8.
  7. HD7 CHECK THE FUEL INJECTORS AND HARNESS FOR AN OPEN 
    • PCM connector disconnected.
    • Measure the resistance between:
      ( + ) PCM Connector, Harness Side ( - ) PCM Connector, Harness Side
      VPWR Suspect INJ

    Is the resistance between 11 - 18 ohms? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . GO to PINPOINT TEST H step 46 .
  8. HD8 CHECK THE FUEL PRESSURE 
    WARNING: THE FUEL SYSTEM REMAINS PRESSURIZED WHEN THE ENGINE IS NOT RUNNING. TO PREVENT INJURY OR FIRE, USE CAUTION WHEN WORKING ON THE FUEL SYSTEM.
    • Key ON, engine running.
    • Start and run the engine at idle, Check and record the FUELP.
    • Fuel pressure gauge connected.
    • Increase the engine speed to a minimum of 2,000 RPM and maintain for two minutes.
    • Note and compare the fuel pressure.

    Is the fuel pressure within specification? Refer to the fuel pressure chart in  PINPOINT TEST HC  . 

    Yes No
    Key in OFF position.
    GO to  HD9.    		 REFER to the appropriate FUEL SYSTEM article.
  9. HD9 VERIFY THE FUEL SYSTEM HOLDS PRESSURE 
    • Start and run the engine at idle, CHECK the fuel pressure.
    • Increase the engine speed to a minimum of 2,000 RPM and maintain for two minutes.
    • CHECK for fuel leaking at the fuel injector O -ring, fuel pressure regulator, and the fuel lines to the fuel charging assembly.

    Did the fuel pressure remain within 34 kPa (5 psi) for 60 seconds? 

    Yes No
    Key in OFF position.
    GO to  HD10.    		 REFER to the appropriate FUEL SYSTEM article to determine which area within the fuel delivery system is at fault.
  10. HD10 CHECK THE FUEL INJECTORS ABILITY TO DELIVER FUEL 
    NOTE: The fuel delivery system is not likely to have caused the misfire DTC if the flow test is within specification.
    • GO to PINPOINT TEST HC for reference to the warning, caution, and handling to prevent accident.
    • Verify the flow rate for each injector is within specification. Use the injector flow tester.

    Is the flow rate for each injector within specification? 

    Yes No
    GO to  HD11. REPLACE or CLEAN the inoperative fuel injector(s) as required. CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES .
  11. HD11 CHECK THE VACUUM SYSTEM 
    NOTE: Some vacuum leaks can be heard.
    • Visually inspect the vacuum hoses for signs of damage or deterioration. A collapsed vacuum hose may cause a blockage to one of the various actuators or sensors. If a blockage is found remove the blockage or install new parts as necessary.

    Is the vehicle vacuum system OK? 

    Yes No
    GO to  HD12. REPAIR the vacuum system. CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES .
  12. HD12 CHECK THE DAMPER AND PULLEY ASSEMBLY 
    NOTE: This step is for engines that have damper mounted pulse rings. Remove the front cover if necessary to observe the crank pulley.
    • Observe the crank pulley for wobble.
    • Examine the EI pulse ring fastened to the harmonic dampener.

    Does the crank pulley wobble or is the pulse ring loose or damaged? 

    Yes No
    DISCONNECT the battery for 5 minutes to allow the PCM to learn the new profile. REPLACE the pulley or damper assembly. CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES . GO to  HD13.
  13. HD13 CHECK THE EVAPORATIVE EMISSION SYSTEM 
    • The Misfire Monitor can be influenced by the Evaporative Emission system. The next 5 pinpoint test steps diagnose the Evaporative Emission system.
    • CHECK the EVAP canister for fuel saturation.

    Is there an excess amount of liquid fuel present in the canister? 

    Yes No
    REPLACE the EVAP canister. CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES . GO to  HD14.
  14. HD14 PRESSURE TEST THE EVAPORATIVE EMISSION SYSTEM 
    • INSTALL Rotunda Evaporative Emission System Tester 134-00056, or equivalent, first at the EVAP service port. If equipped, then at the fuel filler cap.
    • Follow the test instructions from the tester kit.

    Is the evaporative emission system holding pressure? 

    Yes No
    GO to  HD15. Repair the fault as necessary. CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES .
  15. HD15 CHECK VACUUM IN THE EVAPORATIVE EMISSION SYSTEM 
    • CHECK the vacuum system between the engine vacuum port and the EVAP canister.
    • CHECK the EVAP system lines/hoses (check for proper connections, damage or blockage).
    • CHECK for blockage in the fuel tank vent system.

    Is there a fault indicated? 

    Yes No
    REPLACE the damaged vacuum hoses, or REMOVE the blockage/restrictions. CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES . GO to  HD16.
  16. HD16 CHECK THE EVAP CANISTER PURGE VALVE HOUSING LEAKS 
    • The EVAP canister purge valve is electrically connected.
    • INSTALL a hand vacuum pump to the fuel vapor port from the EVAP canister on the EVAP canister purge vacuum valve at the line.
    • Apply 53 kPa (16 in-Hg) of vacuum with the vacuum pump.

    Does the EVAP canister purge valve hold vacuum at room temperature? 

    Yes No
    GO to  HD17. REMOVE the vacuum pump. REPLACE the damaged EVAP canister purge valve.
    CLEAR the DTCs. REPEAT the self-test.
  17. HD17 CHECK FOR FILTER CONTAMINATION ON THE EVAP CANISTER PURGE VALVE 
    • The vacuum line from the input vacuum port to the intake manifold on the EVAP canister purge valve (the control vacuum solenoid part of the valve) is removed.
    • INSTALL a hand vacuum to the open vacuum port on the EVAP canister purge valve.
    • Apply 48 - 52 kPa (10 - 15 in -Hg) of vacuum to the canister purge valve.

    Does the EVAP canister purge valve hold vacuum, or is the valve very slow to release vacuum to the atmosphere? 

    Yes No
    REPAIR the EVAP canister purge valve filter. If unable to clean the filter or remove blockage to the filter, replace the EVAP canister purge valve.
    CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES .    		 GO to  HD18.
  18. HD18 CHECK FOR BASE ENGINE CONCERNS 
    • This step determines if there are any base engine concerns that may have caused the Misfire DTC or drive concern.
      NOTE: The engine temperature may affect the results.
    • Perform the following tests in order to evaluate base engine integrity:
    • Perform engine compression and leakdown tests.
    • Perform valve train analysis.
    • CHECK the Positive Crankcase Ventilation System.
    • CHECK possible leakage points. REFER to the appropriate ENGINE SYSTEM article for all of the above.

    Is any repair required? 

    Yes No
    REPAIR the fault. REFER to the appropriate ENGINE SYSTEM article for all of the above. GO to PINPOINT TEST Z step 1 .
  19. HD19 CHECK Z1 TO IDENTIFY A FAULT 

    Did Pinpoint Test Z find a fault? 

    Yes No
    CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES . GO to  HD20.
  20. HD20 CHECK FOR ADDITIONAL MISFIRE DTCS 
    • Diagnostic trouble code P0300s indicate multiple cylinders are misfiring or the PCM cannot identify which cylinder is misfiring.

    Are any other misfire DTCs present? 

    Yes No
    GO to  HD1. GO to  HD21.
  21. HD21 CHECK FOR OTHER NON-MISFIRE CONTINUOUS MEMORY DTCS 

    Are other continuous memory DTCs present? 

    Yes No
    GO to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS for pinpoint test direction. REPAIR the other DTCs first. GO to  HD22.
  22. HD22 CHECK THE CAMSHAFT POSITION (CMP) SENSOR TYPE 
    • Identify which type of CMP sensor the vehicle uses.

    Does the vehicle use a Hall-effect sensor? 

    Yes No
    GO to  HD23. GO to  HD24.
  23. HD23 CHECK THE CMP SENSOR LOW RANGE OUTPUT WITH THE PCM DISCONNECTED 
    NOTE: DTCs P1309 and 1336 indicate the misfire monitor is not enabled.
    • PCM connector disconnected.
    • Connect the digital multimeter.
    • Bump the engine with a short burst from the starter, without starting the engine for at least 10 engine revolutions.
    • Measure the voltage between:
    ( + ) CMP Sensor Connector, Harness Side ( - ) 12 Volt Vehicle Battery
    CMP Negative terminal

    Is the voltage less than 2 V? 

    Yes No
    A Hall -type CMP that is installed out of synchronization produces a DTC. To verify the correct installation, REFER to the appropriate ENGINE SYSTEM article. If the CMP is installed properly, INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . REPLACE the CMP sensor. CARRY OUT the misfire monitor repair verification drive cycle. REFER to DRIVE CYCLES .
  24. HD24 CHECK THE CMP SENSOR OUTPUT VOLTAGE 
    • Key in OFF position.
    • PCM connector connected.
    • CMP Sensor connector disconnected.
      NOTE: Diagnostic trouble code P1309 indicates the misfire detection monitor is not enabled.
    • Digital multimeter on low voltage AC scale.
    • Key ON, engine running.
    • Measure the voltage between:
      ( + ) PCM Connector, Harness Side ( - ) 12 Volt Vehicle Battery
      CMP Negative terminal

    Is the voltage greater than 0.25 V? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . INSTALL a new CMP sensor.
  25. HD25 DTC P0315: CHECK THE PHYSICAL CONDITION OF THE CRANKSHAFT PULSE WHEEL 
    NOTE: DTC P0315 is set when the PCM is unable to learn and correct for the mechanical variations in the crankshaft pulse wheel tooth spacing (the allowable correction tolerances are exceeded).
    • INSPECT the crankshaft pulse wheel for damaged teeth.
    • INSPECT the Crankshaft Pulsewheel for wobble.
    • CHECK for a loose Crankshaft Pulse Wheel.
    • CHECK the CKP sensor for damage.

    Are the CKP sensor and Crankshaft Pulse wheel OK? 

    Yes No
    INSPECT the Crankshaft Pulse Wheel. Refer to the appropriate ELECTRONIC ENGINE CONTROLS article if the CMP is installed properly, REPAIR as necessary. Disconnect the battery for 5 minutes to allow the PCM to learn new data.
    GO to PINPOINT TEST Z step 1 .
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