i got automatic nissan serena 2002, the problem is, it doesnt shift smoothly. When I put the lever to D or R, it does not move immediately. It also over rev before shifting to 2nd or 3rd and it moves very hard at low gear specially uphill, it also take a pause before shifting. And the worst part every time I stop at intersection, when step on the pedal it doesnt move just like the gear changed to neutral, it also happens when i slow down on turns.

I just changed the fluid 3 weeks ago, levels are good.

My mechanic says, it's a faulty MAF Sensor. I just need a clever opinion before changing anything because I just found out that my auto man is trying to rip me off by contacting the parts dealer.

Sorry for the bad english, lol