1998 Honda Civix HX, 100000 miles. Runs great except CEL shows misfire cylinder 3. Changed plugs and wires and CEL light blinks after 150 miles. Cannot pass inspection. Mechanic is stumped. Need help and suggestions

 

Please do a search next time and/ or go the Sticky
And yes I do know that you're new to this forum as well.

 

Do a full tune-up first, including a distributor cap and rotor.

It could also be a clogged or defective #3 fuel injector.

Is the alternator belt a Honda OEM belt? Poor quality control on aftermarket alternator belts have been known to set off misfire DTC's in 6G Civics, 96-97 del Sols, and 1G CRV's. Strange, but true.

 

I had intermittant misfiring in cylinder 2 it would occur at sudden acceleration especially at low RPMs, and the 6,000+ RPM Range. A few days later, my car wouldn't start at all, it cranked and everything, but had no spark. I checked the coil, replaced spark plugs, Ignition Control Module (Igniter), distributor and rotor. Took it to a mechanic he was stumped all day, later we found out the ECU ignition circuit went dead.

Maybe you need to get the ECU checked out.