if you really want to learn more about ECU's and open;closed loop check this forum out. not to take away from hho but they tell you alot of info in which you can maximize your hho experience.

this is for people who really want to tune their personal cars and have it run efficient. Most of it is talked about hondas but you will get the idea.

Look under tuning! and READ READ READ

http://wikitest.pgmfi.org/twiki/bin/...ibrary/WebHome