I just wired up an autometer 5 inch tach and the reading is off and i dont know what do to..... for example if my stock tach(which is only a little off) reads 5,000 my autometer reads 1,500.. any ideas... my ground is good i wired everything right... do i have to adjust it somehow???.... by the way this is in a 90 crx....im stuck.... pls help....

THX DAN