Tachometer not working!!

Recently my tachometer started acting up and when I would turn the car on it would be fine then after driving it would suddenly drop to zero and the check engine light would come on then it would go back up and the check engine light would go off etc... until finally it just stays at zero now. I know that there isnt a problem with anything else because the check engine light only comes on when the tach drops to zero. Any help/advice would be greatly appreciated. Thanks

there should be a connection in the back of ur gague cluster where the tach goes and that could be loose i would look there first and just trace that wire for other lose connections, my bet is that is all it is and if all connections are good ur cluster might be going bad and that is all i can think of