Just got done installing my boy'z cylinder head and cleared the error codes so they can recirculate, no dice, the same error codes come up like a with in a minute:
p0325 knock sensor
p020 catalyst
p1164 02 sensor
p1259 vtec malfunction
p1456 evap

I most of missed a sensor, will start with the knock sensor and work my way up. If you have any positive insight, do get at pronto.
Thanks

 

Missed a connector? Are your grounds good? There's 1 from the engine block to the radiator support and 1 behind each fender.

 

Lucky me, the knock sensor was broken. Replace it & Im down to one error code, the dreaded p420.
Anyone?, Im not replacing the cat!

 

Google "spark plug defouler trick".

 

Recheck your valve adjustment, if the exhaust valves are too tight they can cause a misfire or catalyst threshold efficiency code. If the piston tops had some carbon build up then it may just be the new head/sparkplugs are burning off some excess carbon from the piston tops. It should clear up in abut 100miles.