OBD-II Code · Sensors
P0111
IAT Sensor Range/Performance
Severity
low
Lowest on our scale. Fix it when convenient.
Can you drive it
Only if running normally
A short trip to a shop may be reasonable if the light is steady and the car runs normally. Stop safely for a flashing light, severe shaking, overheating, loss of power, or another urgent warning. The code alone cannot confirm safety.
Indicative cost (USD)
$50–$200
Varies by vehicle, diagnosis, parts, and local labor. This is not a repair quote.
IAT readings out of plausible range.
How a shop works this
Work from evidence to part, not the other way round. A code names a circuit or a symptom; it does not name the part that failed.
Note every code that is set, not just this one.
Codes that appear together usually narrow the cause faster than any one of them read alone.
Read the freeze frame — the conditions the fault was recorded under.
Cold or warm, idle or load, road speed and engine speed. A fault that only appears cold is a different fault from one that only appears under load, even with the same code on the scanner.
Confirm the fault is current rather than history.
Clear the code and see whether it returns under those same conditions. A code that does not come back may have been logged during a repair, a flat battery, or a bad connection that has since been disturbed.
Then work the likely-causes list in the order shown.
That order is what a shop checks first for this code — wiring and connections before the component they run to, because a connector costs nothing to inspect and is a common answer.
If the code comes back after a repair, the underlying fault is still there. That is the point to bring in a scanner with live data and freeze-frame, or a shop that has one.
Common symptoms
- Check engine light
- Running slightly off
Likely causes
- Stuck IAT sensorMost common
- Dirty sensor
Read the full diagnostic procedureP0111 means the Intake Air Temperature sensor signal is electrically valid but does not correlate with engine coolant temperature, time since start,…
P0111 means the Intake Air Temperature sensor signal is electrically valid but does not correlate with engine coolant temperature, time since start, and ambient conditions — for example, IAT reading 180F at cold start when ECT is 75F and the engine has been sitting overnight. This is a rationality fault, not a circuit fault.
Cheapest-first ladder
with the engine cold and key-on engine-off, compare IAT, ECT, and ambient air temp on the scan tool — all three should be within 5-10F of each other on a fully cold-soaked vehicle; if IAT reads 50-100F higher than ECT at cold start, the IAT element is heat-soaked or contaminated; on Toyota/Honda where IAT is integrated into the MAF housing, clean the MAF with CRC MAF cleaner ($10) since IAT contamination usually comes from the same source as MAF contamination; on GM trucks where IAT is a separate sensor in the intake tube, pull the sensor and inspect for oil film on the element (PCV system pushing oil mist past the sensor); voltage check at idle on a typical NTC thermistor IAT — 70F ambient should read roughly 2.5-3.0V, 200F intake air during hot-soak should read 0.5-1.0V. P0111 is the code that catches sensor drift before it goes hard-fault, so cleaning is the right first move on most platforms.
Vehicle-specific patterns2003-2009 Toyota Camry/Tacoma/4Runner with integrated MAF/IAT sees P0111 from the same hot-wire contamination that causes P0101, and CRC MAF cleaner…
- 2003-2009Toyota Camry/Tacoma/4Runner with integrated MAF/IAT sees P0111 from the same hot-wire contamination that causes P0101, and CRC MAF cleaner addresses both;
- 2007-2014GM 5.3L Silverado/Sierra sees P0111 from oil mist on the separate IAT sensor in the intake tube from AFM blow-by, requiring sensor clean or replacement;
- 2005-2012Honda Accord/Pilot J-series sees P0111 paired with MAF aging on the integrated MAF/IAT unit;
- 2008-2014VW/Audi 2.0T TSI sees P0111 from the integrated MAP/IAT in the intake manifold drifting high before failing fully.
Estimated repair$10 to $300.
Look up another code
P0111 — frequently asked
What does a P0111 code mean?
IAT readings out of plausible range.
What causes a P0111 code?
Common causes: Stuck IAT sensor; Dirty sensor.
What are the symptoms of a P0111 code?
Typical symptoms: Check engine light; Running slightly off.
Is it safe to drive with a P0111 code?
Only if running normally. A short trip to a shop may be reasonable if the light is steady and the car runs normally. Stop safely for a flashing light, severe shaking, overheating, loss of power, or another urgent warning. The code alone cannot confirm safety. Estimated repair: $50-$200.
How do I diagnose a P0111 code?
Work from evidence to part, not the other way round. A code names a circuit or a symptom; it does not name the part that failed. 1. Note every code that is set, not just this one. 2. Read the freeze frame — the conditions the fault was recorded under. 3. Confirm the fault is current rather than history. 4. Then work the likely-causes list in the order shown.
More free tools