How old oil, full-lock steering and a loose belt affect the bypass valve, repair options and preventive fluid checks.
Despite the spread of electric steering, hydraulic power steering remains the most common system. The pump creates and regulates pressure and protects internal parts from overheating; a failure can affect other components, so it should be dealt with promptly.
- Old or unsuitable oil overheats the pump and wears rubbing parts.
- Holding the wheel at full lock overloads the system.
- Insufficient belt tension causes uneven fluid delivery and steering shocks.
A sticking bypass valve can be repaired by fully rebuilding the pump, flushing it and replacing worn parts; on some models repairability can only be confirmed after diagnosis. To prevent problems, check fluid level and cleanliness in the reservoir regularly.