I used to use Techron but -- for the past 2+ yrs. or so have been religiously using Berryman's B12 AND (when I can get it) "Seafoam".
A can of B12/Seafoam in the gas tank -- when you TOTALLY fill it up that is -- does wonders to keep the engine/fuel system(s) running top notch.
I have noticed that Seafoam causes a LOT more 'smoke' to come out the exhaust -- (in comparison to B12) -- so don't freak out if/when you see it.
Berryman's B12 also saved my A$$ from having to replace the cats (out of warranty). B12 has been keeping the CEL OFF ever since I got the dreaded P0420 code 2+ yrs. ago.
Prior to this I would use Techron and 'Catalytic (Catastropic?) Converter Cleaner' -- but _since then_ I am swearing by B12.
Gerry
P.S. My 'other' car is a 1996 Porsche 993 Coupe and I _also_ use B12/Seafoam when I fill her up too.
