2001 Corvette: Service Bulletin: Whistle Noise From Intake Manifold/Throttle Body (Replace Intake Manifold)

Subject: Whistle Noise From Intake Manifold/Throttle Body (Replace Intake Manifold)
Source: Chevrolet Dealer Technical Service Bulletin
Number: 02-06-01-021

Models: 2001 Chevrolet Corvette with 5.7L Engine (VINs G, S -- RPOs LS1, LS6)

1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Avalanche, Silverado, Sierra, Tahoe, Suburban, Yukon, Yukon XL, Yukon Denali, Yukon Denali XL) with 4.8L, 5.3L or 6.0L Engine (VINs V, T, Z, N, U -- RPOs LR4, LM7, L59, LQ9, LQ4)

Condition:

Some owners may comment on a whistle noise coming from either the intake manifold or the throttle body. The noise is most noticeable between 1100 and 2000 RPM.

Cause:

This condition may be the result of airflow through the intake manifold.

Correction:

Replace the intake manifold with the part listed below. Refer to the Intake Manifold Replacement procedure in the Engine Mechanical - 5.7L sub-section of the Service Manual (SI Document ID #642853).

Parts Information:

Part Number	Description	Qty
88894339	Manifold, Intake	1

Warranty Information:

For vehicles repaired under warranty, use:

Labor Operation	Description	Labor Time
J0250	Manifold, Intake - Replace	Use Published Labor Time

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.