I knew this truck was not going to pass emissions inspection but I ran it through for a baseline. The acceptable range is 220 ppm and this beast is spewing 2400 ppm. The truck has a 4.6 short block from a 2003, rough idle but doesn't die. I changed the plugs and it now has a little smoother idle but not much. My plan is to change the oil/filter change air filter, O2's and retard the timing to smooth the idle. I want to avoid getting new cats just because of cost. I can title it so I don't have to go through inspection but I would like to know if anyone has had any luck lowering hydrocarbons from 10x the acceptable limit.

Thanks

 

check compression to make sure the valves are hanging up and the rotor is good. Seen aftermarket rotors cause all sorts of problems.

 

Thanks, I will give it a look.