we drove down to Texas yesterday to pick up a car for my wife and I thought I was idling my car down but I apparently was turning the wrong screw. When I saw the brown dust all over the back of my car I turned the screw back. Is this a bad sign? What does it mean?

 

If you are going to try to tune the carb, do it the right way. Follow Sterling's suggestions, and you'll know that you have it right. http://sterlingmetalworks.com/tuning_the_nikki.htm

Good luck.




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It's just unburnt fuel. My bumper has a big brown stain right above the muffler tips too. It won't come off. Actually after my first trip down to deal's gap, I wound up with a big brown stain all over the right rear of the car. But that's because I was running really rich.

 

I don't know Chris, might have been from all the oil you were shooting out the exhaust too.

Mine runs pretty rich with the Sterling on it, but it takes a very long time to get any discoloration on the tail end of my car.

 

it's more of a combination of rich mixture and the oily fuel being burnt. perfectly normal.

 

Keep in mind, your car is red, mine is silver. It would show up more easily on my car. Could be oil as well though. Probably a mix of both.

 

so basically its probably from driving 80mph/4k rpm for long distances?