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Home >> Acura >> 2009 >> TSX Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> PGM-FI System (4-CYL) >> DTC Troubleshooting >> DTC P050B: Cold Start Ignition Timing Control System Performance Problem
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DTC P050B: Cold Start Ignition Timing Control System Performance Problem

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )
  1. Turn the ignition switch to ON (II)
  2. Check for Temporary DTCs or DTCs with the HDS

    Are any Temporary DTCs or DTCs other than P050B indicated? 

    YES  -Go to the indicated DTC's troubleshooting I

    NO  -Go to step 3

  3. Check for poor connections or blockage at the intake air duct

    Is it OK? 

    YES  -Go to step 4

    NO  -Reconnect or repair the intake air duct, then go to step  24

  4. Check for damage at the air cleaner housing

    Is it OK? 

    YES  -Go to step 5

    NO  -Replace the air cleaner housing (see AIR CLEANER REMOVAL/INSTALLATION ), then go to step  24

  5. Check for dirt or debris in the air cleaner element

    Is it dirty? 

    YES  -Replace the air cleaner element or remove the debris (see AIR CLEANER REMOVAL/INSTALLATION ), then go to step  24

    NO  -Go to step 6

  6. Let the engine cool until the value of ECT SENSOR 1 is 122°F (50°C) or less
  7. Clear the DTC with the HDS
  8. Start the engine, and let it idle for 10 seconds or more
  9. Monitor the OBD STATUS for DTC P050B in the DTCs MENU with the HDS

    Does the screen indicate FAILED? 

    YES  -Go to step 10

    NO  -If the screen indicates PASSED, intermittent failure, the system is OK at this time If the screen indicates EXECUTING, keep idling until a result comes on If the screen indicates OUT OF CONDITION or NOT COMPLETED, go to step  6

  10. Inspect the ignition timing (see IGNITION TIMING INSPECTION )

    Is the ignition timing OK? 

    YES  -Go to step  12

    NO  -Go to step 11

  11. Check for damage at the CKP sensor (see CKP SENSOR REPLACEMENT ) and the CKP sensor pulser plate (see CKP PULSE PLATE REPLACEMENT )

    Is the CKP sensor and/or the CKP sensor pulser plate damaged? 

    YES  -Replace the CKP sensor (see CKP SENSOR REPLACEMENT ) and/or the CKP sensor pulser plate (see CKP PULSE PLATE REPLACEMENT ), then go to step  6

    NO  -Go to step  31

  12. Do the ETCS TEST in the INSPECTION MENU with the HDS

    Is the THROTTLE ACTUATOR CONTROL VALVE normal? 

    YES  -Go to step 13

    NO  -Replace the throttle body (see THROTTLE BODY REMOVAL/INSTALLATION ), then go to step  24

  13. Start the engine Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, then let it idle
  14. While holding the engine speed at 2,500 rpm for 30 seconds, check the MAF SENSOR in the DATA LIST with the HDS

    Is there about 6 0-74 gm/s (M/T) or 7 0-8 6 gm/s(A/T)? 

    YES  -Go to step 15

    NO  -Replace the MAF sensor/IAT sensor (see MAF SENSOR/IAT SENSOR REPLACEMENT ), then go to step  24

  15. Turn the ignition switch to LOCK (0)
  16. Drain the coolant (see COOLANT CHECK )
  17. Remove ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ), and ECT sensor 2 (see ECT SENSOR 2 REPLACEMENT )
  18. Allow the sensors to cool to ambient temperature
  19. Note the ambient temperature
  20. Connect ECT sensor 1 and ECT sensor 2 to their 2P connectors, but do not install them
  21. Turn the ignition switch to ON (II)
  22. Note the value of ECT SENSOR 1 and ECT SENSOR 2 quickly in the DATA LIST with the HDS
  23. Compare the value of ECT SENSOR 1 and the ambient temperature, and the value of ECT SENSOR 2 and the ambient temperature individually

    Does either sensor differ more than 5 4°F (3 °C) from the ambient temperature? 

    YES  -Replace the sensor that differed more than 5 4 °F (3 °C) from the ambient temperature, then go to step  24

    NO  -Refill the coolant (see COOLANT CHECK ), then check for and repair any problems with the following items Go to step  24

    • Engine compression and cylinder leakdown
    • VTEC system
    • Engine oil
    • A/C system
    • Power steering
  24. Turn the ignition switch to ON (II)
  25. Reset the ECM/PCM with the HDS
  26. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE )
  27. Let the engine cool until the value of ECT SENSOR 1 is 122 °F (50 °C) or less
  28. Start the engine, and let it idle for 10 seconds or more
  29. Check for Temporary DTCs or DTCs with the HDS

    Is DTC P050B indicated? 

    YES  -Check for poor connections or loose terminals at the CKP sensor, the throttle body, the MAF sensor/IAT sensor, ECT sensor 1, ECT sensor 2, and the ECM/PCM, then go to step  1

    NO  -Go to step 30

  30. Monitor the OBD STATUS for DTC P050B in the DTCs MENU with the HDS

    Does the screen indicate PASSED? 

    YES  -Troubleshooting is complete If any other Temporary DTCs or DTCs were indicated in step  29, go to the indicated DTC's troubleshooting

    NO  -If the screen indicates FAILED, check for poor connections or loose terminals at the CKP sensor, the throttle body, the MAF sensor/IAT sensor, ECT sensor 1, ECT sensor 2, and the ECM/PCM, then go to step  1 If the screen indicates EXECUTING, keep idling until a result comes on If the screen indicates OUT OF CONDITION or NOT COMPLETED, go to step  27

  31. Update the ECM/PCM if it does not have the latest software (see ECM/PCM UPDATE ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM )
  32. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE )
  33. Let the engine cool until the value of ECT SENSOR 1 is 122 °F (50 °C) or less
  34. Start the engine, and let it idle for 10 seconds or more
  35. Check for Temporary DTCs or DTCs with the HDS

    Is DTC P050B indicated? 

    YES  -Check for poor connections or loose terminals at the CKP sensor, the throttle body, the MAF sensor/IAT sensor, ECT sensor 1, ECT sensor 2, and the ECM/PCM If the ECM/PCM was updated, substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then go to step  33 If the ECM/PCM was substituted, go to step  1

    NO  -Go to step 36

  36. Monitor the OBD STATUS for DTC P050B in the DTCs MENU with the HDS

    Does the screen indicate PASSED? 

    YES  -If the ECM/PCM was updated, troubleshooting is complete If the ECM/PCM was substituted, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ) If any other Temporary DTCs or DTCs were indicated in step  35, go to the indicated DTC's troubleshooting

    NO  -If the screen indicates FAILED, check for poor connections or loose terminals at the CKP sensor, the throttle body, the MAF sensor/IAT sensor, ECT sensor 1, ECT sensor 2, and the ECM/PCM If the ECM/PCM was updated, substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then go to step  33 If the ECM/PCM was substituted, go to step  1 If the screen indicates EXECUTING, keep idling until a result comes on If the screen indicates OUT OF CONDITION or NOT COMPLETED, go to step  33

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