The MAF sensor, which is properly known as the mass airflow sensor, within the 2003 Audi TT is an important component in maintaining the vehicles fuel efficiently. The sensor measures the amount of air entering the engine at a specific time. The sensor then relays this message to the engine computer, where the computer then adjusts the fuel to air ratio ensuring the vehicle runs efficiently and smoothly. When the sensor begins to fail, it may be clogged and need cleaning. A clogged sensor will not be able to measure the air properly so it's important to clean the sensor immediately to ensure the Audit TT runs smoothly.
Allow the Audi TT to cool while in "park" for a half hour. This will prevent any potential burns due to components being too hot.
Open the bonnet of the Audi and locate the MAF sensor. The MAF sensor is located on the Audi's air intake side of the engine directly behind the air box. If needed, the Audi TT owner's manual will have a diagram of installed components.
Detach the wiring hardness by unhooking it from the sensor; place it to the side. Loosen and remove the two bolts securing the sensor to the mount; use a T-20 torix bit to properly remove the bolts. Using any other tool can cause damage to the mount. Unhook the hose clamp securing the sensor in place. Remove the sensor by pulling it off of the mount.
Spray a generous amount of MAF housing cleaning into and on top of the sensor. Clean the sensor inside and out using a microfiber cloth until all dirt and debris has been removed.
Place the newly cleaned sensor back onto the engine. Secure the sensor in place by replacing the bolts; tighten the bolts using the T-20 torix. Reattach the hose clamp and reconnect the wiring harness. Close the bonnet of the Audi TT.