SLOW RESUME RESPONSE DIESEL DRILL OUT VACUUM RESTRICTOR

The following applies in correcting conditions of sow resume response and delayed engagement on vehicles equipped with 6.2L diesel engines.

The vacuum cruise supply on these vehicles is assembled as follows (see illustration below):

A vacuum pump supplies vacuum to various accessories, the EGR valve, and to the cruise system. The hose leading to the cruise system presently has an inline coupler with a 0.6350mm (.025) restrictor.

To correct slow resume response and delayed engagement, remove the plastic coupler, drill out the 0.6350mm (.025) restriction to 1.7780mm (.070) with a 1.9844mm (5/64) drill bit, then reconnect the system to the original configuration.

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.