Nissan Repair: 2001 Sentra, mass air flow sensor, air flow sensor

Question
Rough idling and sometimes dies. Had codes checked by Autozone and was given codes PO171, 174 and 303. If I change out the sensor where is it located?

Answer
Many things could be causing these codes. There is a campaign for a E.C.M foam removal. I would have to suggest that you contact your local Nissan dealer to see if these campaigns have been completed. Some common things that I have seen with these codes is a mass air flow sensor, also a engine computer failure, sometimes even wiring harness problems. A engine computer is under warranty for 8 years or 80000 miles which ever comes first. It may be higher if its a California spec vehicle. Have the dealer check these items for you first. It will save you time and money trying to replace parts that may be good.