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DTC P1294: Target Idle Not Reached: Testing

    NOTE: MAP Sensor, IAC and/or TP Sensor DTCs present must be diagnosed before continuing with this test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .
  1. Turn ignition on, engine not running. With the DRBIII®, read DTCs. Is the Good Trip counter displayed and equal to zero? If yes, go to next step. If no, go to step  8.
  2. Inspect the Intake Manifold for vacuum leaks. Inspect the Power Brake Booster for any vacuum leaks. Inspect the Closed Crankcase Ventilation system for proper operation or any vacuum leaks. Were any problems found? If yes, repair vacuum leak as necessary. If no, go to next step.
  3. Inspect the Air Induction System for dirty air cleaner, foreign material trapped in the air intake tube, etc. Also check for leaks in the air intake tube connection, air cleaner housing, etc. Were any problems found? If yes, repair or replace as necessary. If no, go to next step.
  4. Turn the ignition off. Disconnect the vacuum line at the Closed Crankcase Ventilation system fixed orifice fitting at rear of valve cover. Install Miller Special Tool (6714) 0.185" air metering orifice into the disconnected vacuum line in place of the fixed orifice fitting. Disconnect the purge hose from the fitting on the throttle body. The purge hose is located on the front of the throttle body next to the MAP sensor. Cap the fitting at the throttle body after the purge hose has been disconnected. Start the engine. Ensure that all accessories are off. Allow the engine to reach operating temperature above 180°F (82°C). With the DRBIII®, in System Tests, perform the Minimum Air Flow function. Is the engine RPM between 500 and 900? If yes, go to step  8. If no, go to next step.
  5. Turn the ignition off. Inspect the throttle body plate carbon build-up or other restrictions. Inspect the throttle linkage for binding and smooth operation. Ensure the throttle plate is resting on the stop at idle. Remove IAC, inspect the pintle and its seating surface inside the throttle body. Were any problems found? If yes, clean and/or replace the throttle body as needed. If no, go to next step.
  6. Ensure ignition is off. Disconnect the PCM harness connectors. Measure the resistance of the IAC Driver circuits from the IAC Motor harness connector to the PCM harness connector. Is the resistance below 5.0 ohms? If yes, go to next step. If no, repair the IAC Driver circuit(s) for an open.
  7. There are no possible causes remaining, replace PCM. Program the new PCM. See PROGRAMMING .
    8. WARNING: When the engine is operating, do not stand in a direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing.
  8. The conditions that set the DTC are not present at this time. The following may help in identifying the intermittent condition. With the engine running at normal operating temperature, monitor the DRBIII® parameters related to the DTC while wiggling the wiring harness. Look for parameter values to change and/or a DTC to set. Review the DRBIII® Freeze Frame information. If possible, try to duplicate the conditions under which the DTC was set. Refer to any Technical Service Bulletins (TSB) that may apply. Visually inspect the related wire harness. Look for any chafed, pierced, pinched, or partially broken wires. Visually inspect the related wire harness connectors. Look for broken, bent, pushed out, or corroded terminals. Were any of the above conditions present? If yes, repair as necessary. If no, test is complete.
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