As far as the claims for cleaning out our catalytic converter I'm not going to believe it. It would have to survive the heat of combustion in the cylinder before it reaches the catalytic converter which isn't very likely.

It may however reduce the amount of soot produced, which in the long run the catalytic converter will clean itself (provided it gets hot enough). Cleaning out the injectors and rest of the fuel system will do this to some extent. Of course just dumping half a quart/liter of transmission fluid into your fuel tank will do this too. Adding soybean oil to your fuel will also reduce soot but will increase NOx emissions a tad.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

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