Engine - Exhaust Odor
90chevy07Subject: EXHAUST ODOR COMPLAINTS
Model and Year: 1986 "M" VAN WITH 4.3L TBI ENGINE (VIN CODE Z) AND AUTOMATIC TRANSMISSION
Number: 86-149
Section: 6E
Date: Sept., 1986
Customer comments may be received regarding a rich exhaust odor on 1986 "M" Vans with 4.3L throttle body injecticn (TBI) engines. This condition can be improved by installing a revised calibration prom as listed below.
SERVICE PROM EMISSION SYSTEM TRANSMISSION
16068877 Federal Automatic
16068926 California Automatic
Use applicable labor operation:
NOTICE: This prom will also reduce cold engine fast idle speeds from approximately 850 RPM to 750 RPM in drive.
Slight odor may still be present during warm-up, severe throttle maneauvers, or after wide open throttle applications. This is characteristic of systems equipped with three way catalytic converters. The vehicle should also be inspected to ensure no intake manifold or exhaust manifold leaks are present.