I have recently noticed especially when its cold I step on the gas pedal and it wont go down unless I press it very hard. Also sometimes if I floor it the car starts to hessitate and doesnt wanna take off. Mind u this is usually only when its cold. i have an aftermarket 65mm TB, I sprayed carb clearner in it and it still does it. When its hot outside its fine, but anyways could this be a problem with the TB's butterfly is it time to get a new TB? I bought it used so I dont know the miles on the TB but the spring on it does show rust.