Had to move 4x8 train layout (HO) out of room for about 2 weeks due to carpet being installed in that room. Layout was turned on the side and had to stay that way for the 2 week period. Layout back in the room now and I tried an engine a moment a go....... it is jerking all the way around the layout. I seem to have good electrical contact all around the track. I did not have this problem 2 weeks ago....dirty track?? What is the best way to clean the track and with what? I have used the eraser track cleaner and without much luck. Engine runs fine...just jerking. Suggestions!!!!!!!