Engine - Servicing Throttle Body to Manifold Gasket
87cad6Bulletin No. T 88-26
File in Group 6C
Number 112
Corp. Ref. No. 816301
Date Sept. '87
SUBJECT: THROTTLE BODY TO MANIFOLD GASKET SERVICE
MODELS AFFECTED: 1988 DE VILLE, FLEETWOOD, ELDORADO AND SEVILLE
Figure 1:
With the introduction of the 4.5L V-8 engine for the 1988 model year, revisions in the throttle body bore diameter have dictated changes in the throttle body to intake manifold gasket. The diameter has changed from 35 mm for the 4.1L V-8 gasket to 43 mm on the 4.5L V-8 (see Figure 1).
Care should be taken in service of the gaskets as they are very similar and could mistakenly be interchanged. Interchanging of the gaskets may result in poor emissions and low fuel economy. The 4.5L throttle body to manifold gasket has an identification tab to help distinguish between the 4.5L and 4.1L gaskets (see Figure 1). In the car, this tab is visible when looked at from over the top of the I.S.C. motor.