P2529 Vacuum Reservoir Pressure Sensor Circuit Intermittent

P2529 covers a vacuum reservoir pressure signal that drops out or jumps for short moments rather than staying wrong. The engine module notices changes faster than a reservoir could physically empty or fill, or brief excursions to the electrical limits that recover again. Loose terminals, a cracked wire flexing with the engine, a harness rubbing on the pump bracket or moisture entering the connector are typical, and the fault often vanishes in the workshop. No maker documents P2529 publicly. CARB still expects circuit monitoring of such comprehensive component inputs, and the reservoir itself is the vacuum store a separate pump keeps up. Steady faults are P2527 and P2528.

Likely causes

Symptoms

• Check engine light comes and goes
• Occasional brief loss of power or boost

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: law.cornell.edu, en.wikipedia.org.