Help! There's Smoke Coming From My Tailpipe! What Does It Mean?

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Your car is like your body: deserving of the best while producing nothing but perfection. But just as you can catch a stomach bug from that cute cashier at Taco Bell who thinks washing hands is optional and find yourself spending three sleepless nights on the throne, your car can develop issues that are only apparent when examining the plumes of smoke coming out of its own odorous tailpipe. Here's a crash course in diagnosing those issues.

For the uninitiated, the exhaust tailpipes on modern, properly running vehicles should not exhibit any signs of smoke when driven. There are three kinds of smoke—white, blue, and black—and here's a basic explanation of what each means:

  • White smoke results from water mixing with the exhaust gases or combustion cycle.
  • Blue smoke results from oil mixing with the exhaust gases or combustion cycle.
  • Black smoke results from an abundance of fuel in the combustion cycle. This is also called "running rich."

You'll find three flow charts below, one for each symptom, so you can diagnose simple tailpipe-emissions issues like the Norse God you are. Keep in mind these charts aren't exhaustive and don't account for every possible variation of car trouble, but they do provide a good idea of where these general problems lie:


Tavarish is the founder of APiDA Online and writes about buying and selling cool cars on the internet. He owns the world's cheapest Mercedes S-Class and a graffiti-bombed Lexus, and he's the apparently the only car enthusiast that has never driven a Miata. He also has a real name that he didn't feel was journalist-y enough, so he used a pen name, and this was the best he could do. You can also follow him on Twitter and Facebook. He won't mind.

Adequate Man is Deadspin's new self-improvement blog, dedicated to making you just good enough at everything. Suggestions for future topics are welcome below.