P0113: Intake Air Temperature Sensor 1 Circuit High

What does the P0113 code mean?

Can you continue to drive your car with it, and what are the aftereffects?

Here is a quick evaluation of the problem!

• P0113 Definition: Intake Air Temperature Sensor 1 Circuit High
• Code type: Generic – P0113 indicates the same problem whether you’re having a Ford, Honda, or Toyota, etc.
• Can I Drive with the P0113 code? Yes. It is not severe, and the car is safe to drive.
• Easy to fix? Intermediate-advanced level.
• Cost: $50-$200 (common)

Read on for detailed information about what P0113 is, its causes, and how to identify and fix it.

Table Of Contents

What Does The P0113 Code Mean?

P0113 is a diagnostic trouble code (DTC) for “Intake Air Temperature Sensor 1 Circuit High”.

The car’s computer sets this code if it detects the Intake Air Temperature (IAT) sensor’s voltage is higher than 4.6V. 

This number tells the computer that the intake air temperature is abnormally low (40°F.)

How Do IAT Sensors Work?

An IAT sensor provides the temperature of the air going to the engine.

The combination of air temperature and air volume indicates air mass.

Based on the data received, PCM adjusts fuel added to the air-fuel ratio.  

The colder the air gets, the heavier it becomes and the higher the IAT output voltage.

The voltage usually ranges from 0.5 to 4.5.

What Will Happen When P0113 Is Set?

If the IAT sensor is missing, the data is 4.6V (- 40°F). That tells the PCM that the temperature is cold (but it’s not). The computer doesn’t believe in that information and enters the Failsafe mode to avoid engine damage.

Instead of working with the incorrect data, the computer chooses a constant number to believe in. Usually, most cars will pick 100°F. This allows the engine to run optimally and with minimal damage.

If the actual intake air temperature goes below 100°F, the air is colder than what the computer knows. That causes more air to be sucked into the engine, which results in a lean condition.

On the other hand, an actual intake air temperature above 100°F makes the air hotter. That means less air gets in the engine, leading to a rich condition. 

None of these conditions are desirable.

P0113: Causes, Symptoms, And How To Fix

Symptoms

P0113 will show the following common symptoms:

• Check engine light comes on
• Engine experience a hard start
• Lower fuel efficiency
• Reduced engine performance – vehicle hesitates to accelerate
• Rough idle

Causes

There are only three main causes for the P0113.

Cause #1: Faulty Or Loose IAT Sensor

If the IAT sensor is faulty or loose, it will be sending incorrect data to PCM. The PCM detects that and sets the P0113 code.

The solution is to replace the faulty IAT sensor or make it tighter in its socket if that was the cause of the malfunction.

Cause #2: Defective IAT Sensor Wiring

IAT sensor data goes to PCM through the signal wire. An open signal circuit will lead to high IAT voltage output.

Check the IAT sensor circuit for open, or loose wires and fix them accordingly. Damaged ones should be replaced.

Cause #3: Faulty MAF Sensor

Some vehicles have the IAT attached to the Mass Air Flow (MAF) sensor. So, when the MAF is gone, the IAT is gone. 

In this case, if the MAF is bad, cleaning or replacing the MAF may fix P0113.

Cause #4: Faulty PCM (rare)

PCM rarely becomes faulty and this should be your last conclusion. The most common problem is a bug in its software or damage resulting from a short circuit, lightning, or impact.

Replacing the PCM is the best option in this case. 

This is a complicated and expensive procedure so you may need a qualified automotive technician to help you.

P0113 Causes Identification: How to Diagnose

Solving the P0113 code problem involves diagnosing the causes, one after the other, and eliminating them. Proceed as follows:

Check The IAT Sensor

Start by visually inspecting the IAT sensor for loose terminal connections and dirt. If that is the case, tighten and clean everything.

The next step is to test the resistance across the IAT sensor terminals. If you get infinity resistant or OL (out of limit) reading, it is faulty. So, replace it. 

In case the IAT is attached to the MAF, locate the IAT thermistor and repeat the above process. 

Check IAT Sensor Wiring

Use an OBD2 scanner to view the live data from the IAT sensor with the sensor removed from its socket. The reading should be  -40°F. 

Repeat the process, but this time short the two pins with a jumper wire. The new value should be maxed out (around 285°F). That shows the IAT sensor wiring has no problems.

If you get different values, there is an issue with the IAT sensor wiring. So, use a wire tracker to find where it is open and fix it appropriately.

Check PCM

After checking both the sensor and its wiring, if they are not the problem, it can be because of the PCM. 

9 out of 10 times, the IAT sensor or its wiring will reveal itself as the problem when you perform the above diagnosis. If it’s not, having a mechanic inspect your PCM is the next thing you should do. 

How Much Does It Cost To Fix The Code P0113?

The cost of fixing the P0113 code varies depending on your car’s make, model, and year. Also, the part to be replaced influences the price tag. 

The most common problem is a faulty IAT sensor, which typically costs $20-$150 to replace by yourself. 

The Estimated Repair Cost Of P0113

Note: The data in this table was collected in June 2022. The actual price depends on many factors, such as your car’s make and year, mechanic’s rate, etc.

You Ask, I Answer

The P0113 code should not make you panic. Your car should still be drivable if it has the failsafe feature, and the cost of fixing it is relatively low, about $20-$150 for replacing the IAT sensor. 

Do you have any hands-on experience with the P0113 code? How did you fix it? How much and how long did it take you? Let us know your responses in the comments.

See ya!

Read more: The 9 Best OBD2 Scanners for 2022: The Only Review You Need