Ls400 Won't Rev Past 4000 Rpm When Driving

[jandb327]

Hi All Have 1996 LS400 318,000 miles and counting awhile back engine would now start up. check engine light on ecode said low performing rbank cat. changed both because gaskit leak

after new wires plugs think it's the fuel pump fuel/Air filter are new. One Tech said trans bad next said air flow needs clean,trans seems fine

Thanks for any help.

John

[steve2006]

1st question will it rev past 4000 when it is in park/neutral?

2nd question is the engine management light still on?