It seems we have two problems here: 1. the noise while accelerating, and 2. system too lean.
1. the noise while accelerating may be caused by an exhaust leak. The leak could be at exhaust manifold (cracked), exhaust manifold gasket, or exhaust pipe.
2. Since you replaced the MAF sensor last year, it is unlikely it is defective if you bought it from a dealer. However, still follow nonego's recommendation: clean it and check for intake air leak. If no leak is found, you may need the replace the intake manifold gasket.
Good luck
