i'm new. i just bought a tach for my 99 civic. does anybody know which wire on the distributor connector reads out the RPM?

 

blue wire

 

i did splice into the blue wire, per my haynes manual, but at idle the tach read either 3000 or 6000 (depending on the setting for no. of cylinders) at idle. also, after i installed it my car died on me a few times for no apparent reason, and that stopped after i cut the wire off. so i'm thinking i got the wrong wire. i did go ghetto style and bought a sunpro tach from pepboyz...

 

try the [-] side of the coil.

 

on the drivers side back corner near the firewall, honda has a wire thats also blue. It is unused, but they have it there for mechanics that need to hook up an external tach. Use that wire and it makes for a cleaner install....It might be a different color, but its one wire just chillen, usually with a rubber cap on the end maybe.