I have replace maf sensor 3 time in 6 weeks.don't know if i'm getting bad ones or not;thing is when i put a new one own it will run great for3 or 4 hundred miles and then stard running bad again.the code i'm getting or po101 po171.Ican un plug the sensor and car will run find i am getting 12 volt from plug.i have been running back and forth to Ga with the car but i think maybe it will leave me on the hightway if i don't find out what roung with it.can i be getting that manny bad sensor;Need help Thanks