Toyota Repair: High Hydrocarbons, incomplete combustion, engine misfire

Question
I have a 1993 v6 Toyota 4-Runner with 232,959 miles and an automatic trans. On my last emissions test the report stated that it was releasing a high amount of hydrocarbons. I suspect that this problem is do to the fact that one of the cylinders valves is stuck or malfunctioning, so the fuel that is not burned and just spills out. Could this be? And how much would a problem like this be to fix?

Answer
Yes, that's the correct analisys, hydrocarbons are simply unburned fuel due to an incomplete combustion condition caused by an engine misfire. The cylinder head should be removed and the leaking valve repaired, this can cost around $1,000-1,200 depending on where the repair is done.