I have a Autometer Carbon Fiber Tach hooked up in a 90 Civic HB DX with a ZC swap. Everytime I get over 4k on the tach, it jumps down to 3k and stays. Also, when I tap the gas, it gets all twitchy and goes all over the place. It's on the 4 cylinder setup also. I used to have an old Autometer Phantom tach, and it was doing the same thing. Does anyone know what could be wrong? Thanks.

 

Could be the distributor. Mine was doing that the other day too, but at 4k. When it got to 4K the needle jumped around everywhere and the car was sputtering. Changed the Distributor and everything worked fine. First check the plugs on the distributor and see if theyre wet, dirty, loose n crap like that.

 

did u cut the right wire loops on the back of the tach for a 4 cylinder motor...??

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Custom Rex &raquo;</TD></TR><TR><TD CLASS="quote">did u cut the right wire loops on the back of the tach for a 4 cylinder motor...??</TD></TR></TABLE>

yea, did you cut the right ones? you're supposed to cut both orange and brown wires. Oh yea, where did you attach the tach signal wire to? I hooked mine up straight to the blue wire coming off one of the distributor plugs