i have to hit the blower motor to make it come on but the speed is very slow
Change your blower motor resistor. Here is a short video: https://www.youtube.com/watch?v=5iLV1URL8Xo If no change in performance, you will have to change out your blower motor as well. Usually when you have to hit the motor to start it, it's a bad motor, but since the speed is stuck on low, I would say replace the resistor first.
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