P0174 code detected but car run very normal

Based on the details that I have provided what else could go wrong. I had the P0174 and P0171 code and cleaned MAF sensor and changed the Air filter. Subsequently code came back as P0174. Tapped on MAF and engine runs normal. PCV valve is good.

Vacuum hoses seem to be good. No hissing.
A/F Bank1 Sensor1 changed and injector/Throttle cleaned by dealer 4 months ago. Platinum sparkplugs changed a year ago by dealer. I am wondering what else can go wrong? Appreciate your answer.
Thanks