OBD-II · Engine and powertrain (P)
P0111
Intake air temperature sensor range/performance
What it means
The intake air temperature reading does not change as expected or disagrees with the other temperature sensors.
Symptoms
- engine warning light
- often no noticeable change; sometimes poorer starting or slightly rough running
- slightly higher fuel consumption
Likely causes, most likely first
| No. | Cause |
|---|---|
| 01 | faulty IAT sensor |
| 02 | sensor contaminated by oil or dirt |
| 03 | sensor displaced or poorly mounted |
| 04 | high resistance in the connector |
What to check, step by step
- 01After the car has stood overnight, compare intake air, coolant and outside temperature in live data: they should be within a few degrees
- 02Inspect the sensor connector and wiring; on many European cars the IAT is built into the MAF or boost pressure (TMAP) sensor
- 03Measure the sensor resistance against temperature and compare with specification
- 04Replace the sensor (or the combined MAF/TMAP sensor) if the wiring is good