Buy OEM Buick Part # 26044959 (26031758). Power Steering Pump. 1987-89, 2.0 liter, from VIN 500001. 1990-96, 2.2 liter. 1990-96, 2.2 liter, all. 1990-96, 2.2 liter, auto trans. 2.0

Pump, Power Steering.
Power Steering Pump. Stamped #26031758. Type 1 is VIN to 500,000. Type 2 is VIN from 500,001.

Power Steering Pump

Fits Beretta, Cavalier, Corsica

1987-89, 2.0 liter, from VIN 500001. 1990-96, 2.2 liter. 1990-96, 2.2 liter, all. 1990-96, 2.2 liter, auto trans. 2.0 LITER, type 2. 2.2 LITER. All Models; 2.2L; Auto Trans. All Models; 2.2L; Manual Trans. All Models; 4 Cylinder; Chevrolet. POWER STEERING, 2.2 liter.
Power Steering Pump - Repair or Replace
If the steering in your Buick whines or groans, or if your steering wheel is hard to turn, you may have a failed power steering pump.