ROUGH IDLE/HES/SURGE ON ACCEL. INTERMITTENT CODE E34/OR E45

VEHICLES AFFECTED: 1990 C, E, K W/4.5L

Some 1990 DeVilles, Fleetwoods, Eldorados and Sevilles may experience a driveability condition described as a rough idle, hesitation or sure on acceleration; or an intermittent code E34 and/or code E45. This conditon may be due to a leaking/kinked vacuum hose from the MAP sensor to the throttle body.

To diagnose this condition:

1. Visually inspect the vacuum hose to the MAP sensor for leaks or restrictions. If necessary, replace the vacuum hose with P/N #9439274 (bulk quantity) or equivalent (i.e. 7/32" diameter and 1-3/4" long).

2. If a visual inspection of the vacuum hose does not find the cause of the problem, refer to the appropriate Service Information Manual (Section 6E, Subsection B, under Symptom Diagnosis); or if code E34 or E45 is present, refer to Section 8D1 for diagnosis.

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.