Intake Air Temperature Circuit Range/Performance Problem
Our emissions expert has put together the following information about the P0111 fault code. We have also included diagnostic procedures you can take to your repair shop if the mechanic is having difficulty analyzing the code.
OBD II Fault Code
- OBD II P0111
Fault Code Definition
The Intake Air Temperature Sensor converts the air temperature into a voltage that is high when the Intake Air is cold and low as the engine warms up. Code P0111 is triggered when there is problem in the signal range from the Intake Air Temperature Sensor to the Powertrain Control Module.
Symptoms
- Check Engine Light will illuminate
- In many cases, no abnormal symptoms may be noticed
- In some cases, the engine may be hard starting and/or get poor fuel economy
Common Problems That Trigger the P0111 Code
- Defective Intake Air Temperature Sensor
- Dirty air filter
- Defective Mass Air Flow Sensor
- Faulty or corroded Intake Air Temperature wiring or connections
Common Misdiagnoses
- Intake Air Temperature Sensor is replaced when the real cause is a dirty air filter
- Intake Air Temperature Sensor is replaced when the real cause is a poor connection or chafed wiring
- Intake Air Temperature Sensor is replaced when the real problem is in the Mass Air Flow Sensor