It sounds like the transmission is slipping. I'd imagine your car is a 4speed automatic?
Does it feel like it's being popped into neutral while driving and then snap back in? Careful not to give it too much gas especially from a dead stop.
After running it for a few, maybe around the block or up the nearest main road and back, take out the transmission oil dip stick and smell it, if it smells bad/burnt, it may be time to replace it.
You can rebuild it but it would be cheaper to replace it than having it rebuilt.
That would be the worst case scenario tho. It could be something as simple as low tranny oil or even bad tranny oil which would require a flush.
Anyone else with more experience can chime in with further details. Hope my advice helps tho.
Last edited by NoLimitz89; 04-27-2013 at 12:37 PM.