P0551: Power Steering Pressure Sensor Circuit Range/Performance

What does P0551 mean?

P0551 is a diagnostic trouble code indicating "Power Steering Pressure Sensor Circuit Range/Performance". The sensor or component is providing readings, but they fall outside the expected operating range. The part may be degraded, contaminated, or experiencing intermittent issues affecting idle control performance.

Symptoms you may notice

• Check engine light (MIL) illuminated on dashboard
• Intermittent warning lights
• Erratic gauge readings

Common causes

• Worn or contaminated idle control component
• Vacuum leak or intake air leak
• Clogged filter or restricted flow
• Intermittent electrical connection issue

What should you do?

This code sits in the steering system. Power assistance can cut out without warning, which makes the wheel go heavy, usually worst at parking and low speeds. Steering itself does not disappear, but the effort changes suddenly. Get it diagnosed before driving.