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

  1. Turn ignition on, with engine off. Using scan tool, read DTCs. If DTC SPECIFIC GOOD TRIP counter is displayed and displayed count is "0", go to DTC P0107: MAP SENSOR VOLTAGE TOO LOW  test. If DTC SPECIFIC GOOD TRIP counter is not displayed or displayed count is not "0", go to next step.
  2. Turn ignition on, with engine off. 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 or Figure . Inspect connector for damaged pins, corrosion and loose terminals. Repair connector as necessary. If connector is okay, turn ignition on, with engine off. Measure voltage between ground and Orange wire at MAP sensor connector. If voltage is more than 4.5 volts, go to next step. If voltage is 4.5 volts or less, repair open in Orange wire between MAP sensor and PCM.
  4. Turn ignition off. Remove MAP sensor and inspect sensor vacuum port 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. Using scan tool, monitor engine vacuum while snapping throttle open and closed. If vacuum drops rapidly to less than one in. Hg, go to next step. If vacuum does not drop rapidly to less than one in. Hg, go to step  8 .
  7. Ensure engine is still idling. 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 or 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, no problem is indicated at this time. Test is complete.
  8. 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 or 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.
  9. 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.
  10. At this time, MAP sensor is assumed to be defective. Replace MAP sensor.
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