POWER STEERING SHUDDER (INSTALL HIGH EXPANSION HOSE)

SUBJECT: POWER STEERING SHUDDER

MODELS AFFECTED: 1989 CAVALIER, CORSICA, BERETTA W/2.0L AND 2.8L ENGINES 1990 CAVALIER, CORSICA, BERETTA W/2.2L, 2.3L, 3.1L ENGINES 1991 CAVALIER, CORSICA, BERETTA W/2.2L AND 3.1L ENGINES

THIS BULLETIN CANCELS AND SUPERSEDES DEALER SERVICE BULLETIN NO 90-326-3B, DATED AUGUST 1990. THE 1991 MODEL YEAR HAS BEEN ADDED AS WELL AS THE CAVALIER AND CORSICA VEHICLES. ALSO, ADDITIONAL INFORMATION HAS BEEN ADDED. ALL COPIES OF 90-326-3B SHOULD BE DISCARDED.

MODELS/YEARS AFFECTED: ---------------------- 1990-91 "J" and "L" w/2.2L (VIN G) engine 1990-91 "J" and "L" w/3.1L (VIN T) engine 1990 "L" w/2.3L (VIN A) engine 1989 "J" and "L" w/2.0L (VIN 1) engine 1989 "J" and "L" w/2.8L (VIN W) engine

CONDITION:

----------- Customers may comment about a shudder, moan or vibration that occurs when turning the steering wheel under the following conditions:

- Vehicle stopped with brake applied (or moving very slowly) - Vehicle in gear - Engine at idle speed

The shudder or moan may occur during parking maneuvers or other situations when the steering wheel is turned while the vehicle is stopped or moving very slowly. It is also sensitive to steering wheel rotational speed as well as engine speed. The shudder is commonly more severe during hot ambient temperatures.

CAUSE:

------ A combination of steering gear valve instability and/or engine firing pulses generating a disturbance that is transmitted through the body structure.

CORRECTION:

----------- Install a "tuned" power steering return hose and/or high expansion pressure hose between the steering pump and gear.

1990-91 "J" w/2.2L VIN G engine 1989 "J" w/2.0L VIN 1 engine ---------------------------------------------------------- This condition may be repaired by installing a "tuned" return hose, P/N 26025260.

J-Cars built during the 1991 model year already have the "tuned" return hose. If a 1990 2.2L J-car already equipped with a tuned return hose, or a 1991 2.2L J-car exhibits the shudder, install a high expansion pressure hose, P/N 26029284.

1990-91 "J" w/3.1L (VIN T) engine 1989 "J" w/2.8L (VIN W) engine ---------------------------------------------------------- Starting with the following VIN breakpoints 1991 vehicles are being built with a new high expansion pressure hose which corrects this condition. Vehicles built BEFORE the VIN breakpoints listed below may be repaired by installing a new high expansion pressure hose, P/N 26026623.

(Lordstown) M7117613

1990-91 "L" w/2.2L (VIN G) engine 1989 "L" w/2.0L (VIN 1) engine ---------------------------------------------------------- This condition may be repaired by installing a tuned return hose, P/N 26006690.

"L" cars built during the 1991 model year already have the tuned return hose. If a 1990 2.2L L-car already equipped with a tuned return hose, or a 1991 2.2L L-car exhibits the shudder install a high expansion pressure hose, P/N 26029284.

1990-91 "L" w/3.1L (VIN T) engine 1989 "L" w/2.8L (VIN W) engine ---------------------------------------------------------- Starting with the following VIN breakpoints, 1991 model vehicles are being built with a new high expansion pressure hose which repairs this condition. Vehicles built before the VIN breakpoints listed below may be repaired by installing a new high pressure expansion hose, P/N 26028229.

(Linden) ME178914 (Wilmington) MY219301

1990 "L" w/2.3L (VIN A) engine ---------------------------------------------------------- Starting with the following VIN breakpoint, 1990 vehicles are equipped with a tuned return hose which helps this condition. Vehicles built before this VIN breakpoint, may be repaired by installing a new "tuned" return hose, P/N 26024663.

(Wilmington) LY223211

Note: If the above hoses do not repair the shudder condition please contact Technical Assistance.

Parts are currently available from GMSPO. Labor Operation Number: Pressure hose E8622 Labor Time: See current Labor Time Guide Trouble Code: 92

Labor Operation Number: Return Hose E8623 Labor Time: See Current labor time guide Trouble Code: 92

Engine VIN Model Model Year Carline Engine Code Years Hose Type P/N VIN Breakpt Note ------- ------ ------ ------ ----------- --------- ------------ ---- J 2.0L/2.2L 1 or G 1989-90 Tuned 26025260 SORP 1991 2 Return ----------------------------------------------------------------------------- J 2.2L LM3 G 1990-91 High 26029284 Service Only 1 Expansion ----------------------------------------------------------------------------- J 2.8L/3.1L W or T 1989-91 High 26026623 1991-M7117613 2 Expansion ----------------------------------------------------------------------------- L 2.0L/2.2L 1 or G 1989-90 Tuned 26006690 SORP 1991 2 Return ----------------------------------------------------------------------------- L 2.2L LM3 G 1990-91 High 26029284 Service Only 3 Expansion ----------------------------------------------------------------------------- L 2.8L/3.1L W or T 1989-91 High 26028229 ME178914/ Expansion MY219301 2 ----------------------------------------------------------------------------- L 2.3 LG0 A 1990 Tuned 26024663 1990 - 2 Return LY223211 -----------------------------------------------------------------------------

NOTE: 1. Use Return Hose P/N 26025260 before trying this new pressure hose. 2. Vehicles built after this breakpoint already contain this hose. 3. Use return hose P/N 26006690 on 1990 vehicles before trying this new pressure hose. IF THE HOSES LISTED DO NOT WORK, PLEASE CONTACT TECHNICAL ASSISTANCE.

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.