e46 shaky when accelerating

hey!
my 2000 323i is shaky when accelerating from rpms lower then 2000.
its all good untill I start pushing it,but once I slam the gas pedall it will shake like twice before reaching 2000 rpms. it feels like a lack of power or something.
changed spark plugs,fuel filter-didn`t help???

any suggestion???

Thanks

fuel pump???