first off i have a 94 civic 4door ex and my tach is acting up. when i first start it it works fine. after about five minutes it sits at about 1.5 grand and stays there unless i rev it up past 4 grand then it shoots up really quick and catches up. it will work right from 4000 to redline but when i let off the gas right back to 1.5 grand any ideas to this problem

 

a buddy of mine had just about the same problem with 93 civic with a b16 swap when then car would hit vtec (5200) the tach would jump around all over the place, but up until then it would work fine he replaced the distributor which fixed this problem and also ran alot better

 

car runs fine it's very smooth i just can't figure this out maybe it's the tach in the cluster is bad