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DTC P1297: No Change In Map From Start To Run: Testing

  1. Turn ignition on. Using scan tool, read DTCs. If DTC P0107: MAP SENSOR VOLTAGE TOO LOW is present, repair DTC P0107 before continuing with this test. See DTC P0107: MAP SENSOR VOLTAGE TOO LOW  . If DTC P0107: MAP SENSOR VOLTAGE TOO LOW is not present, go to next step.
  2. Using scan tool, erase DTCs. Start engine and allow it to idle for 30 seconds. Using scan tool, read DTCs. If DTC P1297: NO CHANGE IN MAP FROM START TO RUN is present, go to next step. If DTC P1297: NO CHANGE IN MAP FROM START TO RUN is not present, go to step  6 .
  3. Turn ignition off. Disconnect MAP sensor connector. See Figure . Disconnect PCM connectors. PCM is located in engine compartment on left front fender, near radiator support. Inspect connectors for damaged pins, corrosion and loose terminals. Repair connectors as necessary. If connector terminals are okay, measure resistance of Orange wire between MAP sensor harness connector and terminal No. 17 at PCM C1 harness connector. See Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Orange wire.
  4. Remove MAP sensor and inspect sensor vacuum port for restrictions. Repair any restrictions as necessary. Inspect intake manifold or throttle body vacuum port and hose for restrictions. Repair any restrictions as necessary. If no restrictions exist, go to next step.
  5. At this time, MAP sensor is assumed to be defective. Replace MAP sensor.
  6. Start engine and allow it to idle. Using scan tool, set engine speed to 1500 RPM and read MAP sensor voltage. Wiggle connectors and wiring harness from MAP sensor to PCM. See Figure . PCM is located in engine compartment on left front fender, near radiator support. If engine stalls or voltage becomes erratic while wiggling wiring harness, repair connectors and wiring harness as necessary where wiggling caused engine to stall or voltage to become erratic. If engine does not stall and voltage does not become erratic, go to next step.
  7. Ensure engine is still idling. Using scan tool, monitor engine vacuum while snapping throttle open and closed. If vacuum drops rapidly to less than one in. Hg, no problem is indicated at this time. If vacuum does not drop rapidly to less than one in. Hg, go to next step.
  8. Turn ignition off. Remove MAP sensor and inspect sensor vacuum port for restrictions. Repair any restrictions as necessary. Inspect intake manifold or throttle body vacuum port and hose for restrictions. Repair any restrictions as necessary. If no restrictions exist, go to next step.
  9. At this time, MAP sensor is assumed to be defective. Replace MAP sensor.
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