Theory Of Operation

WARNING: This page is about a different car, the 2014 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.

The fuel feedback system will maintain a stoichiometric air/fuel mixture, 14.7:1, by modifying the injector pulse width according to the oxygen content of the exhaust gas. The Powertrain Control Module (PCM) makes short term and long term fuel corrections to maintain stoichiometric air/fuel ratio for best Catalytic Converter efficiency. If one or more cylinders do not operate at stoichiometric then the high frequency content of the O2 Sensor will increase. Short term fuel correction is based on Upstream O2 Sensor output and is designed for quick engine response. The long term fuel correction compensated for variations in the engine specifications, sensor tolerances and component aging and is designed to correct rich and lean conditions over a longer period of time.