P0113 — Intake Air Temperature Sensor High Input
What P0113 Means
Your engine computer is getting a voltage signal from the intake air temperature (IAT) sensor that's way too high — basically the sensor is claiming the air coming into your engine is around 40 below zero, and the computer knows that's nonsense.
Common Symptoms
- Check engine light — a lot of the time, that's the only thing you'll notice
- Hard starts, especially on cold mornings
- Rough idle or a little hesitation until the engine warms up
- Worse fuel economy — the computer falls back on a "cold air" guess and runs richer than it needs to
- On engines where the IAT lives inside the MAF sensor, drivability can get rougher across the board
Most Likely Causes — Ranked the Way I Actually Check Them
- Unplugged or loose connector. You'd be surprised. A good chunk of the P0113s that roll into my shop show up right after an air filter change or intake work — somebody bumped the plug or never clicked it back in.
- Corroded or spread connector pins. Moisture gets in, terminals turn green or lose their grip, and the circuit opens up.
- Broken or chafed wiring. That harness lives in a hot, vibrating spot. If the signal or ground wire breaks inside the insulation, you've got an open circuit — and an open circuit is exactly what "high input" means on this code.
- The IAT sensor itself failed open. It's a cheap part and it does fail. Heads up: on a lot of vehicles it's built into the MAF sensor, which changes the price of the fix.
- PCM (engine computer) problem. Genuinely rare. Don't let anybody sell you a computer before the wiring has been proven good.
What I Check First in the Shop
First thing I do is pull up live data and look at the IAT reading with the engine warm. If it says -40 while it's 92 degrees out in my parking lot, I know it's electrical, not a temperature problem. Then I unplug the sensor, put a flashlight on the connector, and do a wiggle test on the harness while watching the scanner. If I jumper the two terminals at the plug and the reading slams to the opposite extreme, the wiring and the computer are fine — the sensor's the problem. That whole check takes maybe ten minutes, and it's saved plenty of my customers from paying for parts they didn't need.
Can You Keep Driving?
Honestly, yes — short term. When this code sets, the computer stops trusting the sensor and plugs in a default value, so the engine keeps running. You'll likely burn a little more gas, and cold starts can get cranky. What I don't like about ignoring it: while the check engine light is on for P0113, you won't know if a second, more serious code shows up behind it, and running rich for months isn't kind to your catalytic converter. No need to panic today — just don't sit on it.
Rough Cost: DIY vs Shop
Broad, honest ballparks — every vehicle is different:
- DIY: If it's just the connector, this can be free, or a few bucks of contact cleaner. A standalone IAT sensor is usually a cheap part — often somewhere in the $15–60 range — and most are held in by two screws or a quarter-turn twist. If yours is built into the MAF sensor, the part jumps to roughly $100–400 depending on the vehicle.
- Shop: Expect a diagnostic charge plus the repair. A straightforward sensor swap or connector fix usually lands in the low hundreds all-in. Wiring repairs vary a lot — it depends entirely on where the break is and how buried the harness is.
Scan It Yourself Before the Shop Visit
This is exactly why I built Auto AI Diagnostics. Plug in any cheap ELM327 or vLinker Bluetooth adapter — the $30 ones work fine — and the app reads your codes for free. Then AXEL, the AI in the app, looks at YOUR car's freeze-frame data (what the engine was doing the moment the code set) and explains what it means for your specific vehicle, in plain English or Spanish. Walk into the shop already knowing whether you're looking at a $15 sensor or a wiring issue — or knock it out yourself in the driveway.