Anyone who thinks or believes that would actually work, is as dumb as the people selling it. If you have to "trick" the ECU into thinking something, that's not the way to go about doing it; especially with the a/f mixture. Instead of tricking the ECU, why not just advance the timing by rotating the distributor? Then you're not running rich all the time and killing your power and gas mileage. You want to really give it some colder, denser air? Give it some nitrous.