I've got a strange idle problem. The throttle is very hesitant coming off idle, it takes sometimes up to a second or two before it starts to ramp up. It's also "sticking" at the peak. I'll ramp it up to a certain RPM, and let off the accelerator, but it hovers at that peak RPM for a second or two before s-l-o-w-l-y easing back down to idle. I've tried new TPS and AFS, also made sure the cold start injector wasn't always on. Exhaust system is clear. I'm stumped, HELP PLEASE!!!