How to Clean an Audi TT MAF Sensor

1. Remove the air box by removing the two Philips head screws at the rear of the airbox. There are also tabs that hold it in place.
2. Before removing the air box, disconnect the Secondary Air Injection (SAI) hose, which goes into the lower part of the airbox.
3. The wiring harness is attached to the MAF with a plug. To disconnect it, simply press gently on the plastic knob and pull the plug off of the MAF. Tuck it away somewhere safe.
4. The MAF is attached to the airbox with two Philips head screws. Place a rag under the MAF to catch the screws in case they fall. Remove the screws and place them somewhere safe.
5. Loosen the clamp on the Turbo Inlet Pipe (TIP) and push the pipe down and out of the way of the MAF. The factory original pipe is held on with a self-squeeze clamp. These are removed with a set of large arc joint pliers. These may have been replaced with conventional hose clamps, which simply loosen with a screwdriver.
6. Carefully pull the MAF out of and away from the airbox and then out of the turbo inlet pipe. This may take some wiggling to do it safely. Do not damage the MAF.
7. The screen of the MAF should be readily visible. Spray cleaner on the screen, sensor and the plug area. Wipe off any cleaner that does not dry off.
8. Reinstall the MAF in the reverse order of removal, ensuring that everything is fastened snugly to avoid any air leaks.