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Engine - Chirpy/Ticking/Knocking Noises: Overview

File In Section: 6 - Engine

Bulletin No.: 87-61-20

Date: March, 1998

Subject:
Accessory Drive Noise
(Follow Diagnostic Procedures)

Models:
1998 Cadillac DeVille, Eldorado, Seville, Commercial Chassis
1998 Oldsmobile Aurora with 4.OL, 4.6L Engine (VINs C, V, 9 - RPOs L47, LD8, L37) Built Prior to February 1, 1998

Condition

Some owners may comment about chirping, ticking, knocking, or "trashy" noises from the front of the engine. The service writer and technician should note in writing on the Repair Order the conditions associated with the noise such as outside ambient and engine operating temperatures, and when the noise is observed. The service writer should personally observe and describe the type and location of noise on the Repair Order. The noise may sound like an under hood squeak, a metallic trashy noise, or an inside vehicle thump, etc. The service writer should ask the owner if the noise occurs following start up after an overnight soak, and whether the noise reduces or goes away completely as the engine warms up. Write the customer response on the Service Repair Order.

Cause

This condition may be caused by pulley misalignment of the accessory drive system.

Parts Information

When performing this operation use the information shown:

Part Number Description

12555239 Accessory drive belt -
Seville only

12560973 Accessory drive belt -
Cadillac except Deville without
KG9 option and Seville

12560974 Accessory drive belt -
Cadillac with KG9 option

12561088 Accessory drive belt -
Oldsmobile Aurora

Parts are currently available from GMSPO.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation Description Labor Time

T2267 Accessory Drive 1.3 hrs (E/K Cars)
Service 1.6 hrs (G Cars)