Audi Air Charge Temperature Sensor - Genuine Audi 079919501D

Product Information

An Air Charge Temperature (ACT) sensor, also known as an Intake Air Temperature (IAT) sensor, measures the temperature of the incoming air before it enters the engine’s intake manifold. This sensor helps the engine control module (ECM) optimize air-fuel mixture, timing, and fuel injection, especially during cold starts or high-load situations. A correct air temperature reading is essential, as colder air is denser (requiring more fuel) and hotter air is less dense.

• Poor Engine Performance: A faulty ACT sensor can send incorrect temperature data to the ECM, leading to a lean or rich air-fuel mixture, which can cause sluggish performance, hesitation, or lack of power, particularly when accelerating
• Reduced Fuel Efficiency: Inaccurate air temperature readings may cause the engine to run too rich (too much fuel) or too lean (too little fuel), which can lead to decreased fuel efficiency
• Rough Idle: When the ACT sensor fails, the ECM may not properly adjust the air-fuel mixture for idle conditions, leading to rough or inconsistent idling, especially noticeable when the engine is cold

About Genuine Audi

The original parts used by Audi to build your car are available as replacement parts under the “Genuine Audi” brand. Manufactured under the direction of Audi, expect excellent quality and a premium price since these parts are available exclusively through the Audi Dealership network.

You may not realize this, but the parts that make up your Audi are not necessarily manufactured by Audi. No cause for concern, as Audi designs the part, hires a manufacturer, and ensures its quality to you. In fact, many of these manufacturers have been making parts for Audi for decades. In our industry these manufacturers are called OEM (Original Equipment Manufacturers), and these are often brands you recognize, including Lemforder, ZF, Sachs, Bosch, Valeo, Zimmermann, Siemens VDO, Corteco, and more. Don’t be surprised to open that Genuine Audi parts box and find an OEM branded part inside, simply with the addition of an Audi logo.

Be sure to keep an eye out for OE tags on our product pages to quickly identify parts coming direct from OE manufacturers. That extra bit of insight could save you some serious money while shopping! Refer to our OE Academy for further information regarding the OE/OEM tags throughout the site.