Pickup 4WD L4-2559cc 2.6L SOHC (4ZE1) (1988)
EVAP Canister Vacuum Switching Valve: Testing and Inspection
Purge Control Vacuum Switching Valve
1.
Apply battery voltage to vacuum switching valve.
2.
Ensure air does not flow freely through ports "Y" and "Z".
3.
Ensure air flows freely through ports "X" and "Y".
4.
Remove voltage from valve.
5.
Ensure air flows freely through ports "Y" and "Z".
6.
Ensure air does not flow freely through ports "X" and "Y".
7.
If vacuum switching valve does not operate as described, replace switching valve.