We carry replacement MAF sensors for your Porsche 996TT 01-05 car from Porsche Parts Department.  These new style MAF sensors are less sensitive to dirt and dust.  The Porsche MAF is the control unit of your 996TT.  If your MAF has failed due to a poorly designed intake, over oiling a filter, or other issues, you must replace it.  Replacing the MAF is a very easy process.  The MAF sensor is located on the intake tube of the drivers side of the vehicle.  You will need a torx wrench to remove the MAF and then replace it.