Help needed passing Emissions!

royslead said
Lean your fuel mixture a bit if you can. High HC and CO can come from too much fuel. You may want or have to back off the timing a bit as well.

Too lean will bring NOx, If they don't measure for that then its OK.

Do they hold you to an max idle? Sometimes kicking it up to 1000-1100 RPMS will help throughput.

Be sure you drive it 10 miles or so to get the Cats hot. They do take time to get to operating temp.