you say jump as in full speed then nothing. check 2 rec and 5 rec connections are good. look down the side of the big scr1 block you,ll see 2 little black blocks with a couple of screw connection and a spade terminal.i,m sure there is a little bar that connects them. 1 should have a red dot on it ,they look the same but they are different. if all is tight and good, replace them. should stop jumping