For 1990-2009 cars

# E.F.E. HEATER MAY CRACK INSTALL GASKET

#### MODELS AFFECTED: 1985 FRONT WHEEL DRIVE DEVILLES AND FLEETWOODS WITH HT4100 ENGINE

This bulletin provides service information to be used whenever the throttle body is removed on a 1985 Front Wheel Drive Deville or Fleetwood.

On the transversely mounted HT4100, the Early Fuel Evaporation function (EFE) is performed by an ECM controlled electric EFE heater grid, located under the throttle body on the intake manifold. The EFE heater grid incorporates integral throttle body gaskets. During throttle body removal and replacements, the throttle body side of the EFE heater may adhere to the throttle body and crack or peel. This can result in high idle speed, idle surge, hesitation, or poor performance.

When performing throttle body removal and replacements, check the EFE heater gasket surfaces for cracking, chips and flaking that could cause a vacuum leak under the throttle body. If the EFE heater to throttle body gasket surface is damaged, do not scrap the EFE. Use service throttle body gasket P/N 1620870 between the EFE heater and throttle body, see Figure 1. If the EFE to intake manifold surface of the EFE heater is leaking, cracked or peeling, replace the EFE grid - do not apply this gasket.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those 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 a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.