P25EF
Vacuum Pump Control Circuit B Range/Performance
The secondary vacuum pump does not produce the expected vacuum within the commanded run time. Leak in the pump line or worn pump diaphragm reduces output.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Worn diaphragm or vanes inside the pumpCommon
- Cracked vacuum hose or loose connectionPossible
- Sensor element aged beyond calibration windowLess likely
Parts involved
- Vacuum Pump B
- Vacuum Lines
- Vacuum Sensor
P25EF 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.