P0113: The intake air temperature sensor is reading too high
Intake Air Temperature Sensor 1 Circuit High Input
The intake air temperature sensor reads too hot, so the engine may cut power as a precaution. Get it checked within a couple of weeks, and sooner if power drops sharply.
Stop driving and get help if
- The check engine light is flashing
- The temperature gauge runs high, or you see steam (overheating)
- The car loses power, hesitates badly or stalls
- You smell burning or see smoke
- A brake warning light comes on, or the brakes feel different
Pull over as soon as you can, turn the engine off, and call a tow or roadside help.
What it means
The intake air temperature sensor tells the computer how warm or cold the incoming air is, which affects how much fuel to inject. P0113 means the sensor signal voltage is above the maximum expected, which the computer interprets as extremely hot air. In practice, a high-voltage IAT signal almost always means the sensor is disconnected or has an open circuit, since IAT sensors work on a thermistor principle where resistance decreases as temperature increases. A disconnected sensor floats high, not low.
Common causes
- Disconnected or corroded IAT sensor connectorThe most common cause. A loose connector floats the signal to maximum voltage, which reads as extreme heat.
- Failed IAT sensor with open internal circuitA broken thermistor element inside the sensor causes the same floating-high signal as a disconnection.
- Broken signal wire in the IAT harnessA single wire break between sensor and ECM opens the circuit and the signal floats high.
What the fix could involve
From the cheaper fix to the bigger one. Prices depend on your car, your area and the shop, so ask for a written quote that names the part and the labor before you approve it.
- IAT sensor replacement
- Wiring or connector repair
Symptoms
- Check engine light on
- Slightly reduced power under load (computer derates timing)
- Slightly worse fuel economy
- No obvious driveability complaints in mild weather
What to do next
Unplug the IAT sensor connector and inspect it for corrosion or loose pins. Plug it back in firmly and clear the code. If it returns, use a multimeter to measure sensor resistance at ambient temperature. Most IAT sensors read between 2,000 and 4,000 ohms at room temperature. Infinite resistance means the sensor is open and needs replacement. The sensor is inexpensive and usually takes under 10 minutes to swap.
Lewis shows the live intake air temperature reading so you can see whether it reads an impossible fixed value (indicating open circuit) or fluctuates normally with ambient temperature. Get Lewis on the App Store or Google Play.
Related codes
FAQ
- Is P0113 serious enough to worry about?
- It is low priority compared to fuel or misfire codes, but you should fix it. The engine may reduce ignition timing as a safety measure against assumed hot air, which costs you performance and fuel economy.
- Can P0113 cause engine damage?
- Not directly. The computer compensates by pulling timing to protect against detonation. That compensation itself is not harmful, but it is not correct operation either.
- Can the IAT sensor be inside the MAF sensor?
- Yes, on many modern engines the IAT sensor is integrated into the MAF sensor housing. In that case, P0113 and P0101 may appear together, and replacing the MAF sensor unit fixes both.
Check your car's recalls free. No scanner needed.
Lewis checks your car against NHTSA safety recalls by year, make and model. It is free and works before you own a scanner.