P0111
Intake Air Temperature Sensor 1 Circuit Range/Performance Bank 1
Fuel & air metering
Generic OBD-II
Low
What it means
P0111 means the intake air temperature (IAT) sensor's reading is out of its expected range or doesn't respond correctly as conditions change. The ECM uses air temperature to fine-tune fuel and timing. A skewed reading can slightly richen or lean the mixture, but on its own it has little effect on how the car actually drives.
Low
Can I keep driving? Yes — this is a minor sensor fault; the car drives normally, though cold-start behaviour and fuel economy may be slightly off until it's fixed.
Common symptoms
What you'll notice
- Check-engine light on
- Slightly rough idle or minor hesitation
- Reduced fuel economy
- Air temperature reading on a scan tool that doesn't match ambient or coolant temp
Common causes
Most likely first
- Faulty or lazy IAT sensor (often built into the MAF on many cars)Likely
- Corroded or loose sensor connectorCommon
- Damaged wiring in the sensor circuitCommon
- Sensor contaminated by oil or dirt from the intakeLess often
- Rarely, an ECM faultLess often
How to diagnose & fix
Work through it in order
- Read live data and compare the IAT reading to coolant temp after the car has sat overnight — they should be close.
- Inspect and clean the sensor and its connector.
- Check the wiring for damage or corrosion.
- Replace the IAT sensor (or combined MAF/IAT unit) if the reading stays out of range.
- Clear the code and confirm the reading tracks correctly.
FAQ
Quick answers
Is it safe to drive with P0111?+
Yes. P0111 is a low-impact sensor fault that won't leave you stranded. It's worth fixing to keep fuel trims and cold starts correct, but it isn't urgent.
Can I just clear P0111?+
It may clear briefly, but if the sensor or wiring is at fault the code returns after the ECM re-checks the reading.
Related codes
Often seen with P0111
Read & clear P0111 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX