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Intake Air System (v6) Acura TSX II

Mechanical 25 illustrations ~2874 words

Scheme 1

Scheme 1: Component Location Index
Scheme 1: Component Location Index

DTC P1077: IMT Valve Stuck in High RPM Position

Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

Scheme 2

Scheme 2: DTC P1077: IMT Valve Stuck in High RPM Position
Scheme 2: DTC P1077: IMT Valve Stuck in High RPM Position

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Scheme 10
Scheme 10
  1. Turn the ignition switch to ON (II).
  2. Clear the DTC with the HDS.
  3. Do the IMT TEST in the INSPECTION MENU with the HDS. Is the result OK? YES -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the IMT actuator and the PCM. NO -Go to step 4 .
  4. Turn the ignition switch to LOCK (0).
  5. Disconnect the IMT actuator 5P connector.
  6. Turn the ignition switch to ON (II).
  7. Measure the voltage between IMT actuator 5P connector terminal No. 1 and body ground. Is there about 5 V? YES -Go to step 12 . NO -Go to step 8 .
  8. Turn the ignition switch to LOCK (0).
  9. Jump the SCS line with the HDS.
  10. Disconnect PCM connector C (49P).
  11. Check for continuity between IMT actuator 5P connector terminal No. 1 and PCM connector terminal C11. Is there continuity? YES -Go to step 36 . NO -Repair open in the wire between the PCM (C11) and the IMT actuator, then go to step 30 .
  12. Measure the voltage between IMT actuator 5P connector terminal No. 3 and body ground. Is there about 5 V? YES -Go to step 17 . NO -Go to step 13 .
  13. Turn the ignition switch to LOCK (0).
  14. Jump the SCS line with the HDS.
  15. Disconnect PCM connector B (49P).
  16. Check for continuity between IMT actuator 5P connector terminal No. 3 and PCM connector terminal B19. Is there continuity? YES -Go to step 36 . NO -Repair open in the wire between the PCM (B19) and the IMT actuator, then go to step 30 .
  17. Turn the ignition switch to LOCK (0).
  18. Jump the SCS line with the HDS.
  19. Disconnect PCM connector C (49P).
  20. Check for continuity between IMT actuator 5P connector terminal No. 2 and PCM connector terminal C15. Is there continuity? YES -Go to step 21 . NO -Repair open in the wire between the PCM (C15) and the IMT actuator, then go to step 30 .
  21. Check for continuity between PCM connector terminal C48 and body ground. Is there continuity? YES -Repair short in the wire between the PCM (C48) and the IMT actuator, then go to step 30 . NO -Go to step 22 .
  22. Check for continuity between PCM connector terminal C49 and body ground. Is there continuity? YES -Repair short in the wire between the PCM (C49) and the IMT actuator, then go to step 30 . NO -Go to step 23 .
  23. Check for continuity between IMT actuator 5P connector terminal No. 5 and PCM connector terminal C48. Is there continuity? YES -Go to step 24 . NO -Repair open in the wire between the PCM (C48) and the IMT actuator, then go to step 30 .
  24. Check for continuity between IMT actuator 5P connector terminal No. 4 and PCM connector terminal C49. Is there continuity? YES -Go to step 25 . NO -Repair open in the wire between the PCM (C49) and the IMT actuator, then go to step 30 .
  25. Remove the IMT actuator (see «IMT ACTUATOR REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6) ).
  26. Move the IMT valve by hand. Does it move smoothly? YES -Go to step 27 . NO -Remove the intake manifold upper cover (see «REMOVAL»(/acura/tsx/ii-2008-2014/remont/exhaust/#intake-manifold-and-exhaust-system-v6) ), and repair the stuck valve. If needed, replace the intake manifold (see «INTAKE MANIFOLD REMOVAL AND INSTALLATION»(/acura/tsx/ii-2008-2014/remont/exhaust/#intake-manifold-and-exhaust-system-v6) ), then go to step 30 .
  27. Substitute a known-good IMT actuator (see «IMT ACTUATOR REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6) ).
  28. Turn the ignition switch to ON (II).
  29. Do the IMT TEST in the INSPECTION MENU with the HDS. Is the result OK? YES -Replace the original IMT actuator (see «IMT ACTUATOR REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6) ), then go to step 30 . NO -Go to step 36 .
  30. Reconnect all connectors.
  31. Turn the ignition switch to ON (II).
  32. Reset the PCM with the HDS.
  33. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#idle-control-system-v6__pcm-idle-learn-procedure) ).
  34. Check for Pending or Confirmed DTCs with the HDS. Is DTC P1077 indicated? YES -Check for poor connection's or loose terminals at the IMT actuator and the PCM, then go to step 1 . NO -Go to step 35 .
  35. Monitor the OBD STATUS for DTC P1077 in the DTCs MENU with the HDS. Does the screen indicate PASSED? YES -Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 34 , go to the indicated DTC's troubleshooting. NO -If the screen indicates FAILED, check for poor connections or loose terminals at the IMT actuator and the PCM, then go to step 1 . If the screen indicates NOT COMPLETED, keep idling until a result comes on.
  36. Reconnect all connectors.
  37. Update the PCM if it does not have the latest software (see «PCM UPDATE»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#pgm-fi-system-v6__pcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#fuel-and-emissions-systems-v6__substituting-the-pcm) ).
  38. Start the engine, and let it idle without load (in P or N) until the radiator fan comes on.
  39. Check for Pending or Confirmed DTCs with the HDS. Is DTC P1077 indicated? YES -Check for poor connections or loose terminals at the IMT actuator and the PCM. If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#fuel-and-emissions-systems-v6__substituting-the-pcm) ), then go to step 38 . If the PCM was substituted, go to step 1 . NO -Go to step 40 .
  40. Monitor the OBD STATUS for DTC P1077 in the DTC's MENU with the HDS. Does the screen indicates PASSED? YES -If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#pgm-fi-system-v6__pcm-replacement) ). If any other Pending or Confirmed DTCs were indicated in step 39 , go to the indicated DTC's troubleshooting. NO -If the screen indicated FAILED, check for poor connections or loose terminals at the IMT actuator and the PCM. If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#fuel-and-emissions-systems-v6__substituting-the-pcm) ), then go to step 38 . If the PCM was substituted, go to step 1 . If the screen indicates NOT COMPLETED, keep idling until a result comes on.

DTC P1078: IMT Valve Stuck in Low RPM Position

Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).

Scheme 11

Scheme 11: DTC P1078: IMT Valve Stuck in Low RPM Position
Scheme 11: DTC P1078: IMT Valve Stuck in Low RPM Position

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Scheme 15
Scheme 15
  1. Turn the ignition switch to ON (II).
  2. Clear the DTC with the HDS.
  3. Do the IMT TEST in the INSPECTION MENU with the HDS. Is the result OK? YES -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the IMT actuator and the PCM. NO -Go to step 4 .
  4. Turn the ignition switch to LOCK (0).
  5. Disconnect the IMT actuator 5P connector.
  6. Turn the ignition switch to ON (II).
  7. Check the IMT VALVE SW in the DATA LIST with the HDS. Is CLOSE indicated? YES -Go to step 12 . NO -Go to step 8 .
  8. Turn the ignition switch to LOCK (0).
  9. Jump the SCS line with the HDS.
  10. Disconnect PCM connector B (49P).
  11. Check for continuity between PCM connector terminal B19 and body ground. Is there continuity? YES -Repair short in the wire between the PCM (B19) and the IMT actuator, then go to step 24 . NO -Go to step 31 .
  12. Turn the ignition switch to LOCK (0).
  13. Jump the SCS line with the HDS.
  14. Disconnect PCM connector C (49P).
  15. Check for continuity between PCM connector terminal C48 and body ground. Is there continuity? YES -Repair short in the wire between the PCM (C48) and the IMT actuator, then go to step 24 . NO -Go to step 16 .
  16. Check for continuity between PCM connector terminal C49 and body ground. Is there continuity? YES -Repair short in the wire between the PCM (C49) and the IMT actuator, then go to step 24 . NO -Go to step 17 .
  17. Check for continuity between IMT actuator 5P connector terminal No. 5 and PCM connector terminal C48. Is there continuity? YES -Go to step 18 . NO -Repair open in the wire between the PCM (C48) and the IMT actuator, then go to step 24 .
  18. Check for continuity between IMT actuator 5P connector terminal No. 4 and PCM connector terminal C49. Is there continuity? YES -Go to step 19 . NO -Repair open in the wire between the PCM (C49) and the IMT actuator, then go to step 24 .
  19. Remove the IMT actuator (see «IMT ACTUATOR REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6) ).
  20. Move the IMT valve by hand. Does it move smoothly? YES -Go to step 21 . NO -Remove the intake manifold upper cover (see «REMOVAL»(/acura/tsx/ii-2008-2014/remont/exhaust/#intake-manifold-and-exhaust-system-v6) ), and repair the stuck valve. If needed, replace the intake manifold (see «INTAKE MANIFOLD REMOVAL AND INSTALLATION»(/acura/tsx/ii-2008-2014/remont/exhaust/#intake-manifold-and-exhaust-system-v6) ), then go to step 24 .
  21. Substitute a known-good IMT actuator (see «IMT ACTUATOR REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6) ).
  22. Turn the ignition switch to ON (II).
  23. Do the IMT TEST in the INSPECTION MENU with the HDS. Is the result OK? YES -Replace the original IMT actuator (see «IMT ACTUATOR REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6) ), then go to step 24 . NO -Go to step 32 .
  24. Reconnect all connectors.
  25. Turn the ignition switch to ON (II).
  26. Reset the PCM with the HDS.
  27. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#idle-control-system-v6__pcm-idle-learn-procedure) ).
  28. Start the engine, and let it idle without load (in P or N) until the radiator fan comes on.
  29. Hold the engine speed at 4,000 rpm for 3 seconds or more, then let it idle.
  30. Check for Pending or Confirmed DTCs with the HDS. Is DTC P1078 indicated? YES -Check for poor connections or loose terminals at the IMT actuator and the PCM, then go to step 1 . NO -Go to step 31 .
  31. Monitor the OBD STATUS for DTC P1078 in the DTCs MENU with the HDS. Does the screen indicates PASSED? YES -Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 30 , go to the indicated DTC's troubleshooting. NO -If the screen indicates FAILED, check for poor connections or loose terminals at the IMT actuator and the PCM, then go to step 1 . If the screen indicates NOT COMPLETED, go to step 28 .
  32. Reconnect all connectors.
  33. Update the PCM if it does not have the latest software (see «PCM UPDATE»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#pgm-fi-system-v6__pcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#fuel-and-emissions-systems-v6__substituting-the-pcm) ).
  34. Start the engine, and let it idle without load (in P or N) until the radiator fan comes on.
  35. Hold the engine speed at 4,000 rpm for 3 seconds or more, then let it idle.
  36. Check for Pending or Confirmed DTCs with the HDS. Is DTC P1078 indicated? YES -Check for poor connections or loose terminals at the IMT actuator and the PCM. If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#fuel-and-emissions-systems-v6__substituting-the-pcm) ), then go to step 34 . If the PCM was substituted, go to step 1 . NO -Go to step 37 .
  37. Monitor the OBD STATUS for DTC P1078 in the DTC's MENU with the HDS. Does the screen indicate PASSED? YES -If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#pgm-fi-system-v6__pcm-replacement) ). If any other Pending or Confirmed DTCs were indicated in step 36 , go to the indicated DTC's troubleshooting. NO -If the screen indicated FAILED, check for poor connections or loose terminals at the IMT actuator and the PCM. If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#fuel-and-emissions-systems-v6__substituting-the-pcm) ), then go to step 34 . If the PCM was substituted, go to step 1 . If the screen indicates NOT COMPLETED, go to step 34 .

Throttle Body Test

Note. If the malfunction indicator lamp (MIL) has been reported on, check for diagnostic trouble codes (DTCs).

Scheme 16

Scheme 16: Throttle Body Test
Scheme 16: Throttle Body Test
  1. Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
  2. Turn the ignition switch to ON (II).
  3. Make sure the HDS communicates with the PCM. If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#pgm-fi-system-v6__dlc-circuit-troubleshooting) ).
  4. Start the engine. Hold the engine speed at 3,000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.
  5. Check the REL TP SENSOR in the DATA LIST with the HDS. The reading should be below 2.46 percent. If it is not, clean the throttle body (see «THROTTLE BODY CLEANING»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6__throttle-body-cleaning) ).

Throttle Body Cleaning

CAUTIONDo not insert your fingers into the installed throttle body when you turn the ignition switch to ON (II), or while the ignition switch is in ON (II). If you do, you will seriously injure your fingers if the throttle valve is activated.

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Scheme 17
Scheme 17

Scheme 18

Scheme 18
Scheme 18
  1. Make sure the ignition switch is turned to LOCK (0).
  2. Check for damage to the air cleaner element. If the air cleaner element is damaged, replace it (see «AIR CLEANER ELEMENT INSPECTION/REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6) ).
  3. Remove the throttle body (see «THROTTLE BODY REMOVAL/INSTALLATION»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6__throttle-body-removalinstallation) ).
  4. Clean off the carbon from the throttle valve and inside the throttle body with a paper towel soaked in throttle plate cleaner. NOTE: Remove the throttle body to clean it. Be careful not to pinch your fingers. To avoid removing the molybdenum coating, do not clean the bearing area of the throttle shaft (A). Do not spray throttle plate cleaner directly on the throttle body. Use Acura genuine throttle plate cleaner.
  5. Install the throttle body (see «THROTTLE BODY REMOVAL/INSTALLATION»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6__throttle-body-removalinstallation) ).
  6. Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
  7. Turn the ignition switch to ON (II).
  8. Reset the PCM with the HDS.
  9. Select the ETCS TEST in the INSPECTION MENU with the HDS.
  10. Select TP POSITION CHECK and clear the throttle position (TP) learned value.
  11. Turn the ignition switch to LOCK (0).
  12. Turn the ignition switch to ON (II), and wait 2 seconds without pressing the accelerator pedal.
  13. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#idle-control-system-v6__pcm-idle-learn-procedure) ).

Scheme 19

Scheme 19: Air Cleaner Removal/Installation
Scheme 19: Air Cleaner Removal/Installation
  1. Do the battery removal procedure (see «RECONNECTION»(/acura/tsx/ii-2008-2014/remont/body-electrical/#battery-v6__reconnection) ).
  2. Disconnect the MAF sensor/IAT sensor 5P connector (A).
  3. Remove the harness clamps (B) and the bolt (C).
  4. Loosen the band (D), then remove the air cleaner housing (E).
  5. Install the parts in the reverse order of removal. NOTE: After you torque the hose clamp screw (F), make sure the clearance (G) is less than 0.04 in (1.0 mm).
  6. Do the battery installation procedure (see «RECONNECTION»(/acura/tsx/ii-2008-2014/remont/body-electrical/#battery-v6__reconnection) ).

Scheme 20

Scheme 20: Air Cleaner Element Inspection/Replacement
Scheme 20: Air Cleaner Element Inspection/Replacement
  1. Open the air cleaner housing cover (A).
  2. Remove the air cleaner element (B) from the air cleaner housing (C).
  3. Check the air cleaner element for damage or clogging. If it is damaged or clogged, replace it. NOTE: Do not use compressed air to clean the air cleaner element.
  4. Clean and remove any debris from inside the air cleaner housing.
  5. Install the parts in the reverse order of removal. If you did not replace the air cleaner element, this procedure is complete. If the Maintenance Minder required air cleaner element replacement, reset the Maintenance Minder (see «RESETTING THE MAINTENANCE MINDER»(/acura/tsx/ii-2008-2014/remont/reset-procedures/#maintenance-v6__resetting-the-maintenance-minder) ). If the idle speed fluctuates, do the idle speed inspection (see «IDLE SPEED INSPECTION»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#idle-control-system-v6__idle-speed-inspection) ).

Scheme 21

Scheme 21: Intake Air Resonator Removal/Installation
Scheme 21: Intake Air Resonator Removal/Installation

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Scheme 24
Scheme 24
  1. Remove the air intake cover (A).
  2. Remove the PCM (see «PCM REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#pgm-fi-system-v6__pcm-replacement) ).
  3. Remove the air cleaner (see «THROTTLE BODY CLEANING»(/acura/tsx/ii-2008-2014/remont/mechanical/#intake-air-system-v6__throttle-body-cleaning) ).
  4. Remove the battery base (A).
  5. Remove the intake air ducts (A).
  6. Remove the front bumper (see «FRONT BUMPER REMOVAL/INSTALLATION»(/acura/tsx/ii-2008-2014/remont/exterior-body-panels/#bumpers-v6__front-bumper-removalinstallation) ).
  7. Remove the intake air resonator (A).
  8. Install the parts in the reverse order of removal.
  9. Do the battery installation procedure (see «RECONNECTION»(/acura/tsx/ii-2008-2014/remont/body-electrical/#battery-v6__reconnection) ).

Scheme 25

Scheme 25: IMT Actuator Replacement
Scheme 25: IMT Actuator Replacement
  1. Disconnect the IMT actuator 5P connector (A).
  2. Remove the bolts (B) and the IMT actuator (C).
  3. Install the parts in the reverse order of removal with a new O-ring (D).

Throttle Body Removal/Installation

CAUTIONDo not insert your fingers into the installed throttle body when you turn the ignition switch to ON (II), or while the ignition switch is in ON (II). If you do, you will seriously injure your fingers if the throttle valve is activated.
  1. Make sure the ignition switch turned LOCK (0).
  2. Disconnect the MAP sensor connector (A).
  3. Remove the intake air duct (B).
  4. Disconnect the throttle body connector (C).
  5. Disconnect and plug the water bypass hoses (D), then remove the throttle body (E).
  6. Install the parts in the reverse order of removal with a new gasket (F).
  7. Refill the radiator with engine coolant (see «COOLANT REPLACEMENT»(/acura/tsx/ii-2008-2014/remont/cooling-fan/#engine-cooling-system-v6) ). NOTE: NOTE: If it is in case of replacing or cleaning the throttle body, go to step 8. If it isn't, this procedure is complete.
  8. Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
  9. Turn the ignition switch to ON (II).
  10. Reset the PCM with the HDS.
  11. Select the ETCS TEST in the INSPECTION MENU with the HDS.
  12. Select TP POSITION CHECK and clear the throttle position (TP) learned value.
  13. Turn the ignition switch to LOCK (0).
  14. Install the parts in the reverse order of removal with a new gasket (F).
  15. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tsx/ii-2008-2014/remont/testing-diagnostics/#idle-control-system-v6__pcm-idle-learn-procedure) ).

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