P0106
PowertrainManifold Absolute Pressure/Barometric Pressure Circuit Range/Performance Problem
The MAP (manifold absolute pressure) or BARO (barometric pressure) sensor is reporting values outside the expected range or that don't make sense for the engine's running condition. The sensor itself may be faulty, or there's a vacuum issue affecting its readings.
ⓘ Information only. This page provides general educational information about fault code P0106. We do not assess the urgency or safety implications of any specific fault. That requires in-person diagnosis by a qualified mechanic. Full terms.
Recommended next steps
Whether a fault is urgent, drivable, or routine depends entirely on the cause on a specific vehicle, and that can only be determined by a qualified mechanic with diagnostic equipment. If a warning light is illuminated, the most reliable next step is professional diagnosis.
What does P0106 mean?
P0106 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance Problem.
This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.
Symptoms commonly associated with this code
Symptoms that drivers often report alongside this code. Not all may apply to every case:
- • Engine warning light
- • Hesitation or stumbling under acceleration
- • Rough idle, sometimes with a hunt or surge
- • Poor fuel economy
- • Sometimes hard starting at altitude (the BARO function helps with cold-start fuelling)
- • Black smoke under load on diesels
- • Possibly limp mode if the ECU loses confidence in the load reading
Possible causes
Causes commonly associated with P0106, listed in approximate order of typical investigation. The actual cause on a specific vehicle can only be confirmed by professional diagnosis.
- 1. Failed MAP sensor reading inaccurately (most common, sensors fatigue with age)
- 2. Vacuum hose to the MAP cracked, disconnected, or perished, on cars where the sensor is remote and reads via a hose
- 3. Carbon-fouled sensor port on direct-injection engines, the port to the sensor gets blocked with carbon and gives false readings
- 4. Wiring damage between sensor and ECU
- 5. Connector contaminated, dirty pins or moisture
- 6. Genuine vacuum leak elsewhere in the engine that's affecting load readings
- 7. On a few cars: failed altimeter component within the BARO function
How mechanics typically diagnose
A typical diagnostic sequence used by mechanics, provided here for educational reference only. Diagnostic work should be performed by a qualified mechanic with the appropriate tools and training.
- 1. Read live data on MAP/BARO readings against engine load. At idle the sensor should read around 25-35 kPa absolute (varies by altitude); at WOT it should approach atmospheric (95-100 kPa)
- 2. Inspect the vacuum hose to the sensor (where applicable) for cracks or detachment
- 3. Check the sensor connector and wiring
- 4. Inspect the sensor port for carbon contamination, particularly on direct-injection engines
- 5. Test the sensor electrically against spec using a hand vacuum pump applied to the port
- 6. Check for vacuum leaks elsewhere that could be affecting load calculations
Common questions about P0106
Will my fuel economy be obviously worse? +
Often yes. The MAP sensor is one of the primary inputs to fuel quantity calculations. A failed sensor can cause the engine to run rich or lean depending on its failure mode. Expect 10-25% worse economy until fixed.
Could this be a vacuum leak rather than the sensor? +
Yes, vacuum leaks affect the same readings the MAP sensor reports. If you have other lean codes (P0171, P0174) alongside P0106, suspect a vacuum leak rather than the sensor. Smoke testing the intake (£30-£60 at independent garage) finds vacuum leaks reliably.
Could a remap have caused this? +
Possibly. Aggressive tunes sometimes push MAP readings outside the sensor's normal range under high boost, particularly on diesels. Have the tune reviewed if the code appeared after remapping.
Information only, not professional advice
The information on this page is provided for general guidance and educational purposes only. It is not a substitute for diagnosis or repair advice from a qualified mechanic. Always verify any fault before paying for repairs. carfaultcodes.co.uk accepts no liability for decisions made based on this information. Full terms →