P0111: the intake air temperature reading doesn't add up
The intake air temperature sensor tells the engine control unit how warm the air entering the engine is, which affects exactly how much fuel it adds for a given amount of air. This code means the sensor's reading doesn't make sense against the engine's other signals, even though the signal itself looks electrically fine. It's a plausibility fault: the number isn't impossible, just not one the computer believes.
You might notice
- The engine warning light comes on
- The engine may run slightly rich or lean until the signal is trusted again
- intake air temperature sensor
- — a sensor that tells the computer how warm the air entering the engine is
What the code itself says
P0111 is a powertrain (engine, gearbox and drive system) code, and the 0 after the letter means it is a generic code with a standard meaning.
Grouped here as: Engine running, fuelling and misfires — Air metering, fuelling, ignition, misfire, idle, boost, knock, oxygen sensors and the catalyst, all working together in the running engine. That grouping is ours, to help explain the code. The code's official family is the letter at the start.
This page is generic. Your car isn't.
A code on its own only tells you what the sensor saw, not what's actually wrong — and that changes next to your other codes. Read this one together with the rest of your scan and we'll work out what's really going on.
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