No doubt in my mind. From what you describe the Intercooler pump,
sometimes called the Auxillary Water Pump, is failing or has failed on your
car. It is an easy job to replace it yourself, or even easier if you have an
extended service contract.

I've had this problem twice (think I was the first to report it) and it can
be a real pain when you want to accelerate quickly and then it just seems
to bog down. Get your IC pump replaced and all should be good. You can
go for the manufacturer pump or get the Johnson pump from someone like
Needswings.

Good luck,

Coyote