Air in the fluid and the loss of the fluid due to fluid leakage can cause the following conditions:

Extremely cold temperatures will cause air bubbles in the system if the fluid level is low.

Inspect the fluid level. Add fluid if necessary. Refer to Checking and Adding Power Steering Fluid .

Inspect for leaks. Refer to Power Steering Gear and Pump Leaks .

If the fluid level is correct, there are no visible leaks, and the fluid still foams, remove the pump from the vehicle and inspect the pump housing for cracks. Refer to Power Steering Pump Replacement .

If you find a crack in the housing, replace the pump.

Bleed the power steering system. Refer to Power Steering System Bleeding .