Will a knock sensor cause a power problem on the car it feals like the car is trying to gain full throttle power but its like something is pulling it back and not letting the car accelerate fast?

In a way, yes. When detonation occurs, you car knocks. Detonation is what it's called when there's gasoline combustion occurs after the normal timing of the engine (after the spark occurs). If your car is properly tuned, i.e. correct timing, has correct plugs that are gapped correctly, etc. then your car can knock, also known as "ping", because of bad gas or overheating (low coolant). What the knock sensor does is retards the timing of the car to help the detonation occur during the proper time. This retardation of timing does have a penalty of lower power. Typically, this power loss is temporary because a knock should only occur a couple of times. If your car knocks a lot, and your knock sensor is constantly retarding your car's timing, you can lose significant power because there is another problem that needs to be addressed. Quite possibly a tank of bad gas.