![]() The engine computer, acting in concert with the engine air flow sensor, electronic fuel injectors, and exhaust oxygen sensor, maintains the stoichiometric ratio for most of your driving. This only works if the engine air/fuel ratio (by mass) is stoichiometric (chemically correct). So what happen to change this? The problem is the three-way (CO, UHC, NOx) catalyst used on engine exhausts. In the old days, under cruising conditions, the engines always ran lean – about 15% excess air - this was economical. It is well known that fuel-lean running improves the efficiency. ![]() ![]()
0 Comments
Leave a Reply. |