OBD-II · Engine and powertrain (P)
P0069
MAP - barometric pressure correlation
What it means
The manifold absolute pressure (MAP) and barometric pressure readings do not have the expected relationship. They should agree with the engine stopped; a throttled petrol engine normally has lower manifold pressure at idle or light load.
Symptoms
- engine warning light
- possible reduced power or poor boost control on turbo engines
- often no noticeable change
Likely causes, most likely first
| No. | Cause |
|---|---|
| 01 | faulty MAP/boost pressure sensor, often fouled with oil or soot |
| 02 | faulty barometric sensor (often inside the ECU) |
| 03 | blocked sensor port or hose |
| 04 | wiring or connector fault |
What to check, step by step
- 01With the key on and the engine off, compare the MAP and barometric readings in live data with local air pressure (about 100 kPa at sea level, lower at altitude)
- 02Remove the MAP sensor and clean oil or soot from the tip and port
- 03Check the sensor wiring, 5 V reference and ground
- 04Replace whichever sensor reads wrong