Senior TN Member
Join Date: May 2012
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 32 Post(s)
Thanked 295 Times in 253 Posts
iTrader Score: 0 reviews
I think if you really want to fine tune your combustion control you would install a carbon monoxide sensor in addition to the oxygen sensor. When you get excess air down to very minimum levels carbon monoxide goes up quite rapidly. The trick is to tune down air until CO starts to go up, but does not spike. Probably can only be done under steady state conditions, and will be frequently overridden by just O2 trim. There is also the emissions to consider. Too little air you make too much CO. Too much air you make too much NOx. But keep in mind Toyota knows all this stuff and more. There is no conspiracy to burn fuel for the oil companies. They are already pushing technology to the limit of current knowledge/technology, and willingness of the customer to pay for it. For example they even have systems which go beyond simple control of fuel air ratio:
"A new water-cooled exhaust gas recirculation (EGR) system helps to ensure the lowest possible emissions at all vehicle speeds and helps increase fuel efficiency. By cooling and controlling exhaust gas injected into each cylinder, the system eliminates the need to richen the air-fuel mixture to control cylinder temperatures."
The government is pushing more and more for fuel economy. One way to do it is to simply reduce engine and HP choices, to bring average fuel consumption down. Auto manufacturers do not want to do that of course. They want to sell bigger and more expensive vehicles, not roller skates with an engine. They are not going to leave any stone unturned, especially the simple ones.
2012 Camry XLE Hybrid
Last edited by Ron AKA; 01-29-2013 at 05:45 PM.