K 3500 Truck 4WD V8-350 5.7L (1988)
Air Injection Hose/Tube: Customer Interest
Engine - Chirping Noise At Idle
GMC NUMBER:
88-T-185
GROUP:
6E - Engine Emissions
DATE:
January, 1989
CORPORATE
NUMBER:
836509R
SUBJECT:
CHIRPING NOISE AT IDLE
MODEL:
1988 C/K 10-30 TRUCKS WITH 5.0L (VIN CODE H) OR 5.7L (VIN CODE K) ENGINES
THIS BULLETIN CANCELS AND REPLACES TRUCK SERVICE BULLETIN 88-T-85 DATED FEBRUARY, 1988, ALL COPIES OF WHICH
SHOULD BE DISCARDED. THIS BULLETIN HAS BEEN REVISED TO CORRECT MODEL APPLICATION.
Some 1988 C/K 10-30 trucks may have been built with incorred Air Injection Reaction System (A.I.R.) check valves and may experience a chirping
noise at idle. This condition may be diagnosed by disconnecting the A.I.R. hoses at the check valves and repeating the condition at which the noise
occurred. If the noise is eliminated, the A.I.R. hoses should be recon-
nected and the check valves should be replaced with check valve, P/N 22050642. Parts are currently available from GMSPO.
Labor Op:
J6090 - Valve, Air Check Replace, Right Side .2 hr
J6091 - Valve, Air Check Replace,
Left Side
.2 hr