Fault code P0113 – a step-by-step guide to diagnosing and fixing it

P0113 is a powertrain DTC which indicates that the voltage signal from the intake air temperature (IAT) sensor is too high. The IAT’s resistance fluctuates based on the temperature. For most IAT sensors, the resistance increases at lower temperatures and decreases as the temperature increases. The powertrain control module sends a 5V voltage to the sensor to monitor these changes. If the return voltage signal is just under or equal to 5V, the control unit triggers the code.

IAT sensor troubles:

• A loose component
• Oxidised connector contacts caused by exposure to moisture and dirt
• Build-ups of oily deposits or other contaminants
• Loose or broken wires

Other possible causes:

• A dirty air filter
• MAF sensor problems
• A faulty PCM

• Difficulty starting the engine. This fault can prevent the system from achieving the right air-to-fuel ratio and cause problems with the timing in the ignition system.
• The engine runs lean or too rich. If the car spark plugs are covered in a blackish substance and smell of fuel, this is a sign that the power unit is running rich. The deposits make it more difficult to ignite the fuel mixture and start the car. The plugs may appear cleaner than normal if the mixture is too lean.
• The check engine light turns on. This just means that an error has been detected and could indicate a wide range of problems. It is important to get a proper diagnosis if this occurs.
• A loss of engine power and poor acceleration. For example, this can occur due to a bad air-to-fuel ratio.

• The first step involves diagnosing the fault which can be done using an ODB2 scan tool. Although this error is often caused by sensor or module malfunction, checking the DTCs using the scanner will enable you to identify any underlying problems. You can connect it to the onboard computer using the data link connector. There are several online resources available to help you decipher these error combinations.
• Next, you should check the condition of the air filter. If it is too dirty or clogged you should replace it before continuing with the diagnostic inspection.
• You can measure the intake air temperature to check whether the IAT thermistor is functioning properly. To do this, you will need to let the engine run for a few minutes to warm it up. Once it's ready, you can check the temperature of the air intake and engine coolant using a temperature gauge. If the intake temperature is lower than the coolant, the conditions are normal. If the temperature is the same or hotter than the coolant, the signal is accurate and the system is overheating.
• Sometimes the sensor can be repaired by removing the contaminants and treating it with a specialised cleaning solution. You may also need to clean the electrical contacts to restore the conductivity. If the wires are damaged, new ones will need to be installed. If the thermistor cannot be fixed it will need to be replaced.
Frequently Asked Questions (FAQ)



What does code P0113 mean?




It indicates that the air intake temperature is outside of the normal range or the IAT sensor isn’t working properly.

Can it disappear by itself?




If it was caused by a technical glitch, it should be automatically removed from the DTC list after 4 successful ignition cycles and erased from the memory archive after 40 cycles.

Can I still drive if the P0113 code appears?




This is not recommended because if the component fails, the engine will go into emergency operation mode. There is also an increased risk of thermal damage and knocking in the engine’s cylinders.