DeVille V8-252 4.1L VIN 8 FI (1983)
Air Injection Check Valve: Technical Service Bulletins
Air Management (A.I.R.) System - Moan or Chirping Noise
Bulletin No. T
86-48
File in Group
6E
Number
26
Corp. Ref. No
805 5667
Date
April '86
SUBJECT:
MOAN OR CHIRPING NOISE FROM A.I.R. SYSTEM DUE TO CATALYTIC CONVERTOR CHECK VALVE
MODELS AFFECTED: 1982-84 DE VILLES, FLEETWOODS AND '85 FLEETWOOD BROUGHAMS EQUIPPED WITH HT4100 ENGINES
Some 1982-84 De Villes, Fleetwoods and 1985 Fleetwood Broughams equipped with HT4100 engines may exhibit a moan or chirping noise from the
A.I.R. system at idle due to the catalytic convertor air injection check valve. A malfunctioning check valve can be identified by pinching off the rubber
hose which feeds air from the air switch valve to the catalytic convertor. If the noise stops when the hose is pinched, replace the catalytic convertor air
injection check valve with P/N 22048209. The new part should be black with a white dot painted on it.
For warranty purposes use labor Operation J6086 for .3 hrs.