Monitor Description
After the engine has been warmed up, the ECM carries out air fuel ratio feedback control, and maintains the air fuel ratio at the theoretical level. In addition, after all the preconditions have been met, active air fuel ratio control is carried out for approximately 30 seconds and during active air fuel ratio control, the ECM measures the response of the air fuel ratio sensor by increasing or decreasing a specific injection quantity based on the theoretical air fuel ratio learned during normal air fuel control. The ECM determines whether there is an air fuel ratio sensor malfunction at the mid-point of active air fuel ratio control.
If the air fuel ratio sensor's response ability is reduced, DTC P014C-00, P014D-00, P014E-00 and P014F-00 are output.
If the air fuel ratio sensor output timing is delayed, DTC P015A-00, P015B-00, P015C-00 and P015D-00 are output.
