Firebird V8-305 5.0L VIN F FI (1987)
CANISTER PURGE VALVE SOLENOID CHECK5.0L (VIN CODE H) GRAND PRIX AND FIREBIRD (CARB)
Test Description:
Numbers below refer to circled numbers on the diagnostic chart.
1.
The solenoid should be pulsing as grounding the diagnostic terminal turns "ON" the solenoid.
2.
Test light should light if CKT 439 is not open as the test light provides a ground for current flow.
3.
Test light is being substituted for solenoid to check if ECM and CKT 428 are OK.
4.
The solenoid is normally open, so vacuum should not be able to be drawn. (Zero inches [0"].)
5.
Applying 12 volts prevents solenoid from pulsing, allowing some vacuum build-up before bleeding "OFF" internally 3" to 5".
6.
The ECM is equipped with a fault protected quad-driver for the canister solenoid so if CKT 428 is not open, the quad-driver is faulty within the
ECM or the connector terminal is faulty. The solenoid coil must measure more than 20 ohms. Less resistance will cause the CCP driver to open
repeatedly.
