To use it increase the speed of your car or vehicle portend you shall achieve your pursuits through personal efforts.
If the accelerator has problem or you were unable to control it in the dream, it is warning you to caution yourself against a particular habit of yours which may turn vice and problematic.
To see an accelerator in your dream symbolizes that time time is right for you to excel in life. You will make all the right decisions yourself in order to advance. It all depends on the mood of your dream as well. If you noticed it stuck suggest that something is blocking you from moving forward. Try and remember who was with you in the dream where it was stuck or jammed.