Is it too rich or too lean or something else?

[brewerbry]

I am stumped again by this car! When accelerating hard, foot to the floor, revs hit 5500 or so and the power drops way off and it feels like the rev limiter kicks in, the tranny stays at the high rpm and does not shift until you slightly let off of the gas. The shift is pretty abrupt once it occurs.

I think it is engine problem but I guess it could be tranny (it is tiptronic with 40,000 miles). I plan to do a tranny service (can't hurt since the records do not show it was ever done).

Any ideas about what else it could be? Running too rich? Too lean? How can you determine the difference?

Car and tranny runs fine just drivjg around town and only acts up when you have fun and step on it.

Thx-