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Manifold Absolute Pressure (MAP) Sensor Not Within Limits

  1. If MAP sensor reading was not within limits of TEST SEQUENCE I, go to next step. If MAP reading is not within limits of TEST SEQUENCE II, go to step  8).
  2. Compare MAP sensor reading with the BP sensor reading of that test. If within 0.75 volts, do not change sensors, they are okay. Variance is due to local air pressure.
  3. If above comparison is not within 0.75 volt of BP reading, check that ignition switch is off and disconnect MAP sensor. Connect Yellow Test Fixture (203814) to wiring harness. Set test selector switch to position "13" and DVOM to "TESTER".
  4. If reading is between 100-250 ohms, go to step 5  ). If outside this range, check Light Green/Black wire from MAP sensor to ECA for a short or open. Also check Black/White wire for a short or open. See Figure. Repair wire(s) and retest.
  5. Set test selector switch to position "12". If reading is between 100-250 ohms, inspect manifold absolute pressure sensor connector. If damaged, repair as necessary. If good, replace MAP sensor and retest. If voltage is still out of limits, replace ECA and retest.
  6. If reading is in step  5) is less than 100 ohms or more than 250 ohms, check Orange/White wire from throttle position sensor to ECA for short or open. Also check Black/White wire for a short or open. See Figure. Repair wire(s) and retest.
  7. Turn test selector switch off and disconnect test equipment. Remove Yellow test fixture.
    NOTE: Steps 8) and  9) are to be used only if MAP reading is not within limits during TEST SEQUENCE II".
  8. If MAP reading is not within limits of TEST SEQUENCE II", turn ignition off. Remove Yellow test fixture from harness. Set DVOM to "2000-OHM" range and check Yellow test fixture resistance.
  9. If resistance is less than 170 ohms or greater than 230 ohms, replace test fixture and repeat TEST SEQUENCE II. If resistance is within 170-230 ohms, carefully align pins of Yellow test fixture with harness and reconnect. Repeat TEST SEQUENCE II.
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