What causes a high HC at idle for a 1987 accord, 2 liter carb? Plugs, wires, cap and rotor changed already.

 

Rich mixture? Sometimes the float valve sticks, overfilling the float bowl.

 

The only thing that would cause high Hydrocardons from the ignition system would be a misfire (skip). Because you don't mention any, then the only other culprit is the carburetor (as Jim mentioned). Japanese carburetors have always been a pain in the a...... (that's why Honda went fuel injection with the lxi and ex as soon as they could). Good luck

P

 

chk for a vacc leak biggest reason for high hc
ck timing, chk vacc adv unit for leak, ,