OBD-II · Engine and powertrain (P)
P0109
MAP/barometric pressure intermittent
What it means
The pressure signal is unstable or drops out.
Symptoms
- occasional hesitation or power loss
- engine warning light that comes and goes
Likely causes, most likely first
| No. | Cause |
|---|---|
| 01 | loose connector |
| 02 | intermittent open or short in wiring |
| 03 | corroded connector terminals |
| 04 | water ingress into connector |
| 05 | intermittent internal sensor fault |
What to check, step by step
- 01Wiggle-test the sensor connector and wiring while watching live data
- 02Check the connector for corrosion, water or loose terminals
- 03Check the 5 V reference and ground for drops
- 04Replace the sensor if the wiring is sound