I've heard some people say that when their ECU is fried they run rich or something. I just put in a new ECU and I guess now I'm kind of paraniod about whether it is working right. I always thought that if it were fried or something that the car would run noticeably bad or not run at all. I got about 2mpg worse on this tank than my old tank, but I drove it slightly harder (hard to say whether gas mileage was actually affected). Any input would be appreciated. Thanks