MAP Sensor Diagnosis

The MAP sensor can cause a variety of driveability problems since it is an important sensor for fuel injection and ignition timing.

Visually check the sensor, connections, and vacuum hose. The vacuum hose should be free of kinks, leaks, obstructions and connected to the proper port.

The VC (VCQ wire needs to supply approximately 5 volts to the MAP sensor. The E2 ground wire should not have any resistance.

Sensor calibration and performance is checked by applying different pressures and comparing to the voltage drop specification. The voltage drop is calculated by subtracting the PIM voltage from the VC voltage.

MAP Sensor Performance Check

The chart is representative of testing the MAP sensor. Voltage drop is calculated. VC voltage - PIM voltage = Voltage drop

Applied

13.3

26.7

40.0

53.5

66.7

Vacuum

kPa

mmHg

100

200

300

400

500

in. Hg.

3.94

7.87

11.81

15.75

19.69

Voltage Drop V

0.3 — 0.5

0.7 — 0.9

1.1 — 1.3

1.5—1.7

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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