Well I obviously have a problem here but I don't know what it is so I'd like some advice please. This has happened to me twice now while on the interstate. I have a 2002 WRX 190k miles stock that has had a few replacements over the years: fuel pump, radiator. I downshift (to 3rd or 4th) to accelerate and my RPMs shoot way up 5-6k but I'm not getting much acceleration. My tires aren't spinning either. What could this be?