GM Service Manual Online
For 1990-2009 cars only

Condition

Cause

Foaming Power Steering Fluid

Inspect the power steering system for air in the power steering fluid. Perform the following procedure if the power steering fluid contains air:

  1. Inspect the power steering system for leaks.
  2. Repair any leaks.
  3. Bleed the power steering system.

Extremely cold weather and low power steering fluid levels will also cause air bubbles in the power steering fluid.