When someone is tailgating me, I downshift and get the rpm's near redline, which causes a rich mixture at WOT, which in turn, results in a large cloud of soot being produced, as I speed off into the wild blue 'yonder
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. I can only guess how much soot the fellow behind me ingested into his cabin...
Needless to say, he will, hopefully, think twice about ever tailgating a car with a TDi badge on it
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.