G 2500 3/4 Ton Van V6-262 4.3L (1986)
Canister Purge Solenoid: Technical Service Bulletins
Canister Purge Solenoid Valve - Inoperative
Number:
86-140
Section:
6D
Date:
AUG., 1986
Subject:
INOPERATIVE ELECTRIC CANISTER PURGE SOLENOID VALVE AND A FALSE CODE 54
Model and Year: 1985-86 G VANS WITH 4.3L, 5.0L, 5.7L ENGINES AND NB2 CALIFORNIA EMISSIONS
TO:
ALL CHEVROLET DEALERS
PURGE SOLENOID VALVE
Some 1985-86 G Vans with NB2 California emissions may experience a shorted out electric purge solenoid valve (See Figure No. 1). This condition
may be caused by moisture entering the electrical portion of the canister purge solenoid valve, setting a false Code 54.
If this condition is encountered and the inspection of the solenoid indicates that replacement of the solenoid is required, replace the purge solenoid valve
and install a new moisture shield, P/N 14066503, which has been released to correct the condition. The electronic control module (ECM) may also have
a failed quad driver in the mixture control solenoid (M/C) circuit and the ECM should be checked to make sure it was not damaged, if the purge solenoid
valve is shorted out. If the ECM is damaged, it also must be replaced.
Removal and installation procedures for the electric canister purge solenoid valve and the ECM are in Section 6E8, Emissions, of the Light Duty Service
Manual.
Before the new moisture shield can be installed, modifications to the purge solenoid valve bracket and moisture shield must be completed.
