Hi, the co and HC give impression of rich mix, does it misfire? Fuel pressure, is it 2.5 bar or higher? Blocked air filter? Leaking ibnjector? Does CO drop dramatically if you diconnect any of the injectors? You could also do a power balance test, keep reves high and disconnect each injector and see which one makes most or least difference.

Too much fuel not enough air but as mentioned few more test results needed to offer help.
HTH James