I bought an 86 toyota truck 22RE rebuilt 10k ago with all paperwork validated previous owner passed smog fine just prior to sale. I just took it to my mechanic and it failed at 15/25 for Carb on Monoxide which I guess means its running rich? and some fuel is getting through. Is this usually a carbeurator issue? I've heard a lot of people getting weber carb rebuild kits because the OEM is a little dirty and inefficient? Could it also be O2 sensor(s).....I'm handy enough to change oil/spark plugs/valve cover gaskets but don't want to dive in to more than I can handle. My mechanic is hesitant to work on carbs and is having a friend look at it and see if they can tinker it through but I have severe doubts that will work.

 

No its not

 

What would you do first nightstalker, can I adjust the mixture on the carb itself?

 

There isn't an oxygen sensor in a carb engine is there? That's for EFI models only which I used to have, isn't it. Any other ideas on what to do to clean up dirty carbon monoxide emissions? Again, the mechanic feels it's running too rich, in the Haynes manual there is only an idle adjust screw section, or replacing/rebuilding the whole carb.