This is a hit or miss technique but for those of you that have MAF issues can go to RadioShack and buy a can of thier electronics cleaner. Spray it heavily on the sensor itself (preferably from as many different angles as possible just not so that the spray runoff travels up the sensor towards the connector). Let it drip dry and do it a few more times with a quick drip dry in between to let the dirt and grime run off. I have brought several MAF sensors with high or low values back using this method. Hey, could be worth the $10 that electronics cleaner costs. If not, I like to keep it on hand anyhow to prep electronics connections as it removes oil and grime left by our hands which is a decent method of corrosion prevention.