Black Smoke with Lean Plugs?
Black Smoke with Lean Plugs? Like title says. Car runs great and pulls hard. Problem is the car smoke black and smells rich, but the spark plugs are white. Can anyone explain this? Here is the tune. Im in OLSD.
Thanks
Thanks
Last edited by 96lt1ss; Mar 23, 2008 at 09:45 PM.
Black is hydrocarbons from some degree of misfire. You can get
there lean or rich. Common cause of the soot out the back is
cat overtemp protection, pushes fuel to 10.5:1 no matter what
your PE fueling is set to when it thinks the cats are seeing too
much temperature.
Plug color tells you more about the average than the maximum
fueling. Maybe you are lean or clean 99% of the time and make
soot 1%. You'll scour them back to white, most likely.
there lean or rich. Common cause of the soot out the back is
cat overtemp protection, pushes fuel to 10.5:1 no matter what
your PE fueling is set to when it thinks the cats are seeing too
much temperature.
Plug color tells you more about the average than the maximum
fueling. Maybe you are lean or clean 99% of the time and make
soot 1%. You'll scour them back to white, most likely.
