Purge Flow Sensor: Testing and Inspection

Purge Flow Sensor Pinout:

PURGE FLOW SENSOR (PFS) INSPECTION
1. Disconnect the vacuum hoses from the PFS.
2. Plug the port leading to the evaporative emission canister purge solenoid valve.
3. Apply 13.6 kPa (4.1 in. Hg) to the PFS.
4. Verify that vacuum holds.
5. Measure the resistance between PFS SIG (Pin 2) and PWR GND (Pin 3) on the PFS.
Resistance: 25.65 - 28.35 ohms

6. Measure the resistance between PFS SIG (Pin 2) and VPWR (Pin 1) on the PFS.
Resistance: 75 - 100 ohms

7. Measure the resistance between VPWR (Pin 1) and PWR GND (Pin 3) on the PFS.
Resistance: 95 - 130 ohms

8. Confirm all wires of PFS vehicle harness have a good connection (i.e., at solder of Red wire). Repair as necessary.
9. If vacuum and/or resistance are not as specified, replace the PFS.