FixVault
Home › Pontiac › 2001 › Aztek Base, AWD › Repair and Diagnosis › Engine Performance › System › Engine Controls Self-Diagnostics › Diagnostic Tests › DTC P0507: Idle Speed - High › Diagnostic Procedures

Diagnostic Procedures

  1. Perform powertrain diagnostic system check. See POWERTRAIN DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check, go to next step.
    2. NOTE: Ensure engine speed stabilizes with each commanded RPM change to determine if engine speed stays within 150 RPM of commanded RPM.
  2. Set parking brake and block drive wheels. Turn off all accessories. Using scan tool in RPM control function, slowly increment engine speed to 1800 RPM then to 600 RPM, then to 1800 RPM. Exit RPM control function. If engine speed stabilizes within 150 RPM of commanded RPM during the test, go to next step. If engine speed does not stabilize within 150 RPM of commanded RPM during test, go to step  4.
  3. Observe FREEZE FRAME/FAILURE RECORDS data for this DTC. Turn ignition off for 30 seconds. Operate vehicle within conditions for running this DTC or as close to FREEZE FRAME/FAILURE RECORDS data observed. See CODE ENABLE CRITERIA . If DTC fails this ignition, go to next step. If DTC does no fail this ignition, see DIAGNOSTIC AIDS .
  4. Turn ignition off. Disconnect IAC valve harness connector. Connect IAC Motor Driver (J-37027-A) to IAC valve. Start engine. Using IAC motor driver, command IAC valve in until about 600 RPM is reached. Command IAC valve out until about 1800 RPM is reached. Return engine speed to desired idle as indicated on scan tool data list. If engine speed steadily decreases to about 600 RPM and steadily increases to about 1800 RPM when IAC valve was commanded in and out, go to next step. If engine speed does not respond as specified, go to step  11.
  5. Turn ignition off. Connect Connector Check Adapter Kit (J-35616-A) to IAC valve harness connector. Using a test light connected to ground, probe one of the IAC valve circuits at connector check Adapter kit. Start engine. Using scan tool, command low RPM while observing a scan tool until IAC counts start to increment. Command high RPM while observing scan tool until IAC counts start to increment. While IAC counts are incrementing, observe test light. Return engine speed to desired RPM as indicated on scan tool data list. Repeat test for the other 3 IAC valve circuits. If test light remains on (never flashing) while IAC counts were incrementing at any of the IAC valve circuits during the test, go to step  10. If IAC counts were not incrementing at any of the IAC valve circuit during the test, go to next step.
  6. If test light remains off (never flashing) while IAC counts were incrementing at any of the IAC valve circuits during the test, go to step  9. If test light does not remain off, go to next step.
  7. Turn engine off. Using connector check Adapter kit, connect test light between IAC coil "A" harness connector terminals "C" (Light Blue/Black wire) and "D" (Light Blue/White wire). Start engine. Using IAC motor driver, command low RPM while observing scan tool until IAC counts start to increment. Command high RPM while observing scan tool until IAC counts start to increment. While IAC counts are incrementing, observe test light. Return engine speed to desired RPM as indicated on scan tool data list. Repeat procedure with test light connected between IAC coil "B" harness connector terminals "A" (Light Green/Black wire) and "B" (Light Green/White wire). Return engine speed to desired RPM as indicated on scan tool data list. If test light stays illuminated (never flashing) while IAC counts were incrementing during the test, go to next step. If test light does not remain illuminated, go to step  15.
  8. Turn ignition off. Check for poor connection at IAC valve harness connector. Repair as necessary. After repairs, go to step  16. If connections are okay, see DIAGNOSTIC AIDS .
  9. Turn ignition off. Disconnect PCM harness connectors. Using DVOM, check for open or short to ground on IAC valve circuit where test light remained off. Repair as necessary. After repairs, go to step  16. If circuit is okay, go to step  12.
  10. Turn ignition off. Using DVOM, check for short to voltage on IAC valve circuit where test light remained illuminated. Repair as necessary. After repairs, go to step  16. If circuit is okay, go to step  12.
  11. Check for throttle body damage and tampering or throttle lever screw tampering, if equipped. Check for vacuum leaks, faulty or incorrectly installed PCV valve and hose, throttle shaft binding, or throttle linkage or cruise control linkage binding, if equipped Remove IAC valve. Check for debris in IAC passage, excessive deposits on throttle plate, throttle bore, or IAC valve pintle. Repair as necessary. After repairs, go to step  16. If no problem is found, go to step  13.
  12. Check for poor connection at PCM harness connectors. Repair as necessary. After repairs, go to step  16. If connections are okay, go to step  14.
  13. Check for poor connection at IAC valve harness connector. Repair as necessary. After repairs, go to step  16. If connections are okay, go to next step.
  14. Replace IAC valve. After replacing IAC valve, go to step  16.
  15. Replace PCM. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  16. Turn ignition on, with engine off. Using scan tool, clear DTCs. Turn ignition off for 30 seconds. Operate vehicle within the conditions for running this DTC. See CODE ENABLE CRITERIA . If DTC runs and passes, go to next step. If DTC resets, go to step  2.
  17. Using scan tool, observe the stored information and CAPTURE INFO. If scan tool displays any undiagnosed DTCs, diagnose affected DTCs. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are displayed, system is okay.
About FixVault