Operation CHARM: Car repair manuals for everyone.
Hosted by mcallihan.com

Emissions - Noise From A.I.R. Valves on Start-up

File In Section: 06 - Engine/Propulsion System

Bulletin No. 99-06-04-002

Date: February, 1999

TECHNICAL

Subject:
Noise From A.I.R. Valves on Start-up (Replace A.I.R. Valves)

Models:
1996-99 Chevrolet and GMC C/K Models, G Vans with A.I.R. Valves and 7.4L Engine (VIN J - RPO L29)

Condition

Some owners may comment on a honking or whining noise that lasts for a few seconds after start-up.

Cause

The air valve goes into resonance due to the air flow through it. This does not affect the ability of the vehicle to meet emissions requirements.

Correction

Install two new A.I.R. valves.

Parts Information

The new valve part number is 12562568. Parts are currently available from GMSP0.

Warranty Information

For vehicles repaired under warranty, use:

Labor 0peration Labor Time

Right
J6090 0.2 hr

Left
J6O91 0.2 hr