Received a P0101 on my Nissan Altima and brought it in to the mechanics. They replaced my MAF sensor and the check engine light was turned off. After about a week, the engine light is back on and fuel efficiently is noticeably impacted. I believe there is a TSB to have ECU rebooted. Could not resetting ECU be a reason why my fuel efficiency is impacted or could there be another issue at hand?
My car has 47000 miles.
My car has an automatic transmission.