P0108: Manifold Absolute Pressure/Barometric Pressure Sensor Circuit High — what it means, the affected system and what to check before replacing parts.
Meaning, symptoms, causes and checks
Manifold Absolute Pressure/Barometric Pressure Sensor Circuit High. Basic catalogue definition; diagnostic details have not yet been reviewed.
Affected system: Powertrain
Symptoms
- Check-engine warning, weak acceleration or irregular idle on some engines.
- A high MAP/BARO electrical signal may affect load calculation even if the actual manifold pressure is normal.
Possible causes
- Short to supply voltage, open ground or damaged sensor connector.
- Faulty MAP/BARO sensor; genuine intake-pressure faults need separate assessment.
What to check
- Confirm P0108 and record freeze-frame; locate the MAP or BARO sensor on the vehicle.
- Check harness, ground and reference supply against OEM diagram.
- Compare MAP and barometric values with the engine off and ignition on; consider ambient pressure.
- Test sensor signal under OEM conditions; distinguish electrical high input from actual high manifold pressure.
- Repair the proven circuit or sensor fault, then verify live data and DTC recurrence.
Also written as: P0108-00, P010800, PO108 (some scan tools add the fault-type byte, e.g. -00).