Torque Converter Problem/Catalytic Converter

I have a 2001 Maxima SE with 74, 200 miles. My check engine light is
on. I took it to my normal independent mechanic because when i "floor
it" on the freeway the rpm's go up but the car doesn't go any faster
for about 7 seconds. Then it takes off. the independent mechanic says
that it is a Catalytic converter problem. I took it to the dealer and
he said it sounded like a torque converter problem. Anyone have any
ideas while I am waiting for the verdict from the dealer?