Manifold Absolute Pressure(MAP)- Testing & Removal 99+

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Manifold Absolute Pressure(MAP) testing & Removal

The MAP monitors intake pressure resulting from engine speed and loads,
which is converted into a voltage output to the PCM.
This varies the voltage signal from closed throtle(high vacum) to wide open throtle(WOT)(low vacum).
The PCM uses the MAP to control fuel delivery and ignition timing.

*performing this will set a DTC and the "check enigne light".
- Clear the codes after tesing and or repairing.

- On 4cyl models the MAP is located on the side of the TB.
- On the V6 the MAP is located on the back side of the upper intake plenum.


- Check the MAP wires and terminals for breaks or being loose.
- Disconnect the elec. connector
and connect the positive lead of a voltmeter to the brown or gray wire terminal on the harness connector.
- Electrical Connector
- Turn the key "ON", the voltage should read approx 5 volts.
- if the voltage is incorrect wiring to the PCM.
- if the cicuits checked OK, have a dealer or other qualified shop test the PCM.

- To check for MAP sensor operations reconnect the sensor connector.
- Using a back probe, back probe the light green wire terminal on the MAP sensor connector.
- Connect the positive lead of the voltmeter to the probe and the negative lead to a good enigne ground.
- Turn the key "ON", and with the engine not running the voltage should be approx. 4-5 volts.
- Start the enigne and allow to idle, the voltage should Decrease to approx. 0.5-0.2 volts.
- if the tests are incorrect replace the MAP sensor.

- Replacing -
- Disconnect the elec. connector and vacum line from the MAP sensor.
- On 4 cyl models, remove the TB mounting bolt then remove the sensor.
- On V6 remove the two retaining screws that hold the MAP to the upper intake plenum brakcet.
- Remove the sensor.
- Install in reverse procedures.