P2526
Vacuum Reservoir Pressure Sensor Circuit Range/Performance
The vacuum reservoir pressure sensor is electrically intact, but the reading does not match the model — vacuum that does not build up after pump activation, does not bleed off when consumers draw, or stays at one value. Often a partly clogged hose, a leaking reservoir or an aged sensor.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Leaking reservoir or vacuum lineCommon
- Aged sensor with offset driftPossible
- Sensor element aged beyond calibration windowLess likely
Parts involved
- Vacuum Reservoir
- Vacuum Lines
- Vacuum Pump
P2526 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.