Hey, (re TBI) Can you try the circuit mentioned in this thread? It should just need a tweak to injhiUS to compensate for the optoisolator lag
http://ecomodder.com/forum/showthrea...tml#post106855
re: Zener, been there, tested it personally with an oscilloscope, no problem, no cause for alarming thread titles, not that a $3 chip is anything to get too alarmed about
http://ecomodder.com/forum/showthrea...html#post73500