stsims

I have a 2006 sc 430 with just over 43,000 miles. The car has always been garaged kept, it is clean inside and out. The question I have is how to tweak the car back to run the way it did when it was newer. What happens to the car is it will hesitate and slug along from the traffic light. If you accelerate at a slow rate when taking off, it is normal. However, if you want to get on it, as soon as you push down the pedal, the engine stumbles all over itself. If you wait for a brief second, it usually recovers, but it can get embarrassing or dangerous. What I have done to overcome this is to " jiggle" the pedal (with my foot of course) and that seems to help. Any suggestions? Thanks