Toyota Repair: HC, air fuel ratio, unburned fuel

Question
I have a 1991 22RE Toy p/u

I tuned it up & took it to smog...

Passed visual, CO2, O2, CO, & NO, but failed HC (62ppm over at 15 MPH and 7ppm over at 25 MPH).

Any ideas what is the likely cause?


Answer
co to high is bad air/fuel ratio

Nox is high combustion camber temp.

Hc too high is unburned fuel.

So you need to be tuned up, get a good set of plugs in there. make sure cap rotor wires are good.
Change the oil.{new oil will absorb some HC}

Mike