P0114Powertrain
Powertrain · SAE
IAT Sensor — Intermittent/Erratic Signal
Meaning
The intake air temperature (IAT) sensor signal fluctuates irregularly in a manner inconsistent with engine operating conditions. The ECU detects anomalous variations that exceed plausibility limits.
Common causes
- Loose, corroded, or intermittent IAT sensor connector
- Damaged or chafed wiring causing intermittent contact
- Deteriorated resistive element inside the IAT sensor
- Electromagnetic interference on the signal circuit
- Poor ground contact at the sensor
Symptoms
- Intermittently illuminated check-engine light
- Transient mixture and power irregularities
- Variable and abnormal fuel consumption
- Starting difficulty under certain conditions
- Fault code that self-clears but returns
Severity
Low to moderate: intermittent faults are difficult to diagnose; if unresolved, may develop into a permanent fault affecting the air/fuel mixture.
What to do
- Inspect the IAT connector: clean contacts and confirm locking
- Check the wiring along its entire run for chafing or loose connections
- Monitor the IAT signal live with a scan tool during a road test
- Measure sensor resistance at different temperatures and compare with the manufacturer's chart
- Replace the sensor or repair the wiring based on findings