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Engine - Poor Driveability After Intake Manifold R & R

89chevy31

Number: 89-205-6A

Section: 6A

Date: July 1989
Subject: ENGINE NOISE/ROUGH IDLE/REDUCED POWER


Model and Year: 1987-89 S/T TRUCK, M VAN WITH 2.5L (VIN CODE E) ENGINE



TO: ALL CHEVROLET DEALERS

THIS BULLETIN CANCELS AND SUPERSEDES BULLETIN 89-161-6A, DATED MAY 1989. ADDITIONAL SERVICE PROCEDURES HAVE BEEN INCLUDED. ALL COPIES OF 89-161-6A SHOULD BE DISCARDED.

Comments regarding rough idle/engine noise/low power following removal of the intake manifold on 2.5L (VIN Code E) engines have been traced to the intake manifold bolt spacer not being reinstalled (see illustration on reverse side for location). The spacer prevents interference between the intake manifold bolt and the # 4 cylinder intake pushrod.

If this condition is encountered, reinstalling the intake manifold bolt spacer in the correct location and replacing the # 4 cylinder intake pushrod will restore engine performance.

If the spacer is missing, a spacer can be made by using two flat washers, P/N 331247 (3/ 8" I.D. x 3/4" O.D. x 1/8"). Place both washers on the bolt, install bolt and torque to 28- 40 N-m (22-30 lbs.ft.).

Parts are currently available from GMSPO.

When making these repairs within the provisions of the vehicle warranty, use:

Labor Operation Number: T7975 "Reinstall Intake Manifold Spacer, and Replace # 4 Intake Push Rod"

Labor Time: M Van - 1.2 Hrs
S/T - .9 Hr