hessitation not slipping into passing gear

[leafjammer]

i have a 2001 nissan maxima and it is an automatic. When i am driving and i want to pass a vehicle my car downshifts then up shifts then downshifts and upshifts you get the idea. It is as if it can not make up its mind so I back off of the gas and just gradually increase my speed. This is very annoying and I am hoping that someone will be able to give me an idea as to what the problem is.

I took it to Nissan and they wanted to start with replacing the fuel pump? I have taken my car to Nissan before and each time they take a shotgun approach, replace several items until it works and then claim it was a compilation of bad parts.
(i can guess too)

Thank you

[loystock]

How's the level and color of the transmission fluid. When was it flushed/replaced? Is there any trouble code. Have you cleaned the MAF sensor before?