| abstract |
Methods, systems and apparatus are provided for detecting moisture in air by using an ammonia sensor contained in the outlet of an engine, such as a diesel engine. In one example, a method for an engine having an outlet with an ammonia sensor includes adjusting an operating parameter in response to ambient humidity, wherein the ambient humidity is based on a first ammonia sensor reading at a first exhaust air / fuel ratio and a second ammonia sensor reading based on a second air / fuel ratio of exhaust gas. |