P0111 code meaning
Intake Air Temperature Sensor 1 Circuit Range/Performance Bank 1
Powertrain system Generic code P01xx codes Check engine light
What P0111 means
Intake air temperature sensor 1 is the first air temperature sensor in the intake path; depending on the vehicle it is built into the mass air flow sensor, mounted near the air filter or, on some naturally aspirated GM engines, fitted in the intake manifold. Most versions are NTC thermistors in a 5 V divider: the hotter the air, the lower the signal voltage. P0111 is a plausibility fault: the signal is electrically valid but does not fit. The usual test runs at key-on after a long soak (Ford 6 h, GM 8 h): the intake air sensor is compared with other temperature sensors such as coolant, cylinder head, charge air cooler or IAT2, which should all read about the same. GM flags it above about 25 °C deviation, Ford above about 17 °C; Ford first confirms with a drive above 40 mph because sunshine can warm a sensor, and also sets P0111 if the air reads over 66 °C while driving. A detected block heater suspends the test. Two consecutive trips are needed.
P0111 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyEasy, DIY possible
- Typical labor0.3 to 1.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P0111
- Check engine light on
- Usually no noticeable symptoms
- Slightly changed idle, power or cold start possible
- Code often returns only after an overnight soak
Common causes of P0111
- Most likelySensor drifting or stuck at one value (ageing, oil from crankcase ventilation)
- PossibleContact resistance at connector or wiring distorts the reading
- PossibleComparison sensor (coolant, IAT2, charge air cooler) wrong
- Less likelyUndetected preheater, heat soak or sensor mounted near a heat source
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Intake air temperature sensorIntake air temperature sensor wiringMass air flow sensor
What each part of P0111 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 1 | Area: fuel and air metering. |
| 11 | The exact fault in that area. |
What to do next
- Note P0111 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0111
What does P0111 mean?
P0111 means "Intake Air Temperature Sensor 1 Circuit Range/Performance Bank 1". Intake air temperature sensor 1 is the first air temperature sensor in the intake path; depending on the vehicle it is built into the mass air flow sensor, mounted near the air filter or, on some naturally aspirated GM engines, fitted in the intake manifold. It is a generic code, so it means the same on every make.
Is it safe to drive with P0111?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P0111 fail an emissions test?
Yes, it can. P0111 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0111 to fix?
Difficulty: easy. A typical repair takes 0.3 to 1.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P0111 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.