Eldorado V8-4.6L VIN 9 (1995)
Canister Purge Solenoid: Testing and Inspection
OPERATION
The Evaporative Emissions (EVAP) System solenoid receives 12 volts from the 10 amp number "D1" fuse on the underhood relay panel through
CKT 741. The Powertrain Control Module (PCM) energizes the EVAP solenoid by grounding pin "3E12" (CKT 428). When the solenoid is
energized it allows the canister to purge.
The canister is commanded to purge when:
^
Maximum of 150 seconds after closed loop is enabled (time varies depending on coolant temperature at key "ON").
^
Coolant temperature is above 80°C (176°F).
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When the PCM is not enabling injector shut-off for Traction Control and Acceleration reduction.
^
Throttle switch is open.
^
Vehicle speed is above 20 mph.
^
Engine speed is greater than 1100 rpm.
^
Engine metal "over temp" coolant condition is not present.
PROCEDURE
1. Attach hose to vapor line that comes from canister to solenoid and attempt to blow into it. Air should not pass into solenoid. If air passes through
solenoid, then replace solenoid.
2. With engine "OFF", go into EVAP solenoid override (PO01). Override of solenoid should cause solenoid to vibrate. Physically touch solenoid
(mounted in engine compartment) in override condition. If solenoid is not vibrating, then replace solenoid.