P1109 Intake Air Temperature Sensor 2 Intermittent
What does P1109 mean on a Ford?
P1109 — Intake Air Temperature Sensor 2 Intermittent. This Ford-enhanced code applies to Supercharged and turbocharged Ford models with dual IAT sensors.
Common causes of P1109
- Loose IAT2 connector at the intercooler outlet
- Heat-damaged IAT2 wiring
- Failing IAT2 sensor
- Corroded terminals
- PCM reference fault
How to fix P1109
- Locate the post-intercooler sensor and inspect its connector
- Wiggle-test while watching live IAT2
- Compare IAT2 to IAT1 on a cold engine
- Check terminals for heat damage
- Replace the sensor if dropouts persist