BARO / MAP Sensor Switching Valve: Testing and Inspection

1. Check pressure VSV system as follows:
a. Connect ECU test harness.
b. Run engine to normal operating temperature.
c. Measure voltage between terminals 38 and 39 while increasing engine speed to 4000 RPM.
d. Depress brake pedal, then release accelerator pedal quickly. Ensure voltage drops momentarily.
e. If voltage fails to drop, check wiring between stop lamp switch and ECU, then perform test again.
2. Check pressure VSV as follows:
a. Connect ECU test harness.
b. Disconnect the vacuum hoses from pressure VSV.
c. Attach a suitable vacuum pump to air cleaner side port and apply 3.94 inches of vacuum. If any vacuum leakage is present, replace the pressure VSV.
d. Turn on ignition switch.
e. Connect terminal 38 with terminal 39. Vacuum gauge should read zero. If vacuum fails to become zero, replace pressure VSV.
f. Apply vacuum to the pressure sensor side port with ignition off. If vacuum can be applied, replace pressure VSV.