Engine - Chirping Noise From At Idle

84pontiac15
Number 84-6 (Gasoline)-49 Date 7/84
Subject: CHIRPING NOISE FROM ENGINE COMPARTMENT AT IDLE - 1982-84 T1000
A "chirping" noise may be experienced from the engine compartment area at idle. This condition may be from the A.I.R. check valve in the air supply line to the catalytic converter.

To determine if this is the case, pinch off the rubber hose between the check valve and the A.I.R. pump while the vehicle is in a fully warmed condition. If the noise stops replace with check valve, Part Number 22048209.