Car is a 93 integra, stock ls motor. When I was bringing it home after buying it, on the highway I noticed that very often the tach needle would quickly drop to 0 then bounce right back up. Its not bouncy when accelerating fyi.

I know thectach gets its signal from the igniter, iirc. Is it an igniter problem or a cluster problem.

 

its gonna most likely be the icm(ignitor) getting weak.