i have a 91 taurus sho, and when im in nuetral and i push the gas more than 1 throttle, it wont rev up. if i floor it it will stay at 3000rpm. i changed the fuel filter, dont have an engine light on, and when i drive it, it shakes really, really bad when i push the throttle fast, but it doesnt die, or missfire. the tps is working properly. i cant find the problem.