Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ). Before you begin, check for poor connections or a blockage at the intake air duct.
- Turn the ignition switch to ON (II).
- Check the MAP SENSOR in the DATA LIST with the HDS. Is less than 54.1 kPa (16.0 in.Hg, 406 mmHg) or 1.61 V held for more than 5 seconds? YES -Go to step 7 . NO -Go to step 3.
- Clear the DTC with the HDS.
- 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.
- Test-drive under these conditions: Engine coolant temperature (ECT SENSOR 1) above 158°F (70°C) Engine speed between 1,400-5,400 rpm A/T in D, M/T in 3rd Vehicle speed accelerated from 16-31 mph (25-50 km/h) under half throttle
- Monitor the OBD STATUS for DTC P1128 in the DTCs MENU with the HDS. Does the screen indicate FAILED? YES -Go to step 7. NO -If the screen indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the MAP sensor and the ECM/PCM. If the screen indicates NOT COMPLETED, go to step 4 and recheck.
- Turn the ignition switch to LOCK (0).
- Replace the MAP sensor (see «MAP SENSOR REPLACEMENT»(ref-355245-S29835499672010012100000) ).
- Turn the ignition switch to ON (II).
- Reset the ECM/PCM with the HDS.
- Do the ECM/PCM idle learn procedure (see «ECM/PCM IDLE LEARN PROCEDURE»(ref-290807-S02808252682008072200000) ).
- 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.
- Test-drive under these conditions: Engine coolant temperature (ECT SENSOR 1) above 158°F (70°C) Engine speed between 1,400-5,400 rpm A/T in D, M/T in 3rd Vehicle speed accelerated from 16-31 mph (25-50 km/h) under half throttle
- Check for Temporary DTCs or DTCs with the HDS. Is DTC P1128 indicated? YES -Check for poor connections or loose terminals at the MAP sensor and the ECM/PCM, then go to step 1 . NO -Go to step 15.
- Monitor the OBD STATUS for DTC P1128 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 14, go to the indicated DTCs troubleshooting. NO -If the screen indicates FAILED, check for poor connections or loose terminals at the MAP sensor and the ECM/PCM, then go to step 1 . If the screen indicates NOT COMPLETED, go to step 12 .