Toyota Repair: Engine light, mass air flow sensor, mass air flow

Question
I have 2005 matrix xr , the engine light is on , code po 171.what is that?

Answer
PO171 is a lean air/fuel mixture condition, usually cleaning the throttle body on the inside as well as the MAF sensor takes care of this code. The inside of the throttle body can be cleansed using a small brush and some air intake cleaner, the mass air flow sensor can be removed from the air intake tube just near the air filter and cleaned using only electronic parts cleaner in a spray can, spray the inside of the opening of the sensor and let it air dry, reinstall it and clear the code by disconnecting the battery for ten seconds.