Peugeot 405

1987-1997 of release

Repair and operation of the car

To minimize the number of pollution which get to the atmosphere some models are equipped with the catalyst in system of release. On all models with the catalyst the system has the closed type where the lambda sensor in system of release reports the ignitions given to system and injection of ECU fuel constant feedback, allowing ECU to regulate mix to provide the best possible conditions for operation of the catalyst.

The lambda sensor has the built-in element of heating operated by ECU via the relay quickly to warm up a sensor tip up to the working temperature. The tip of the sensor is sensitive to oxygen and sends ECU tension changing depending on amount of oxygen in exhaust gases. If fuel-air mix too rich, exhaust gases have the low content of oxygen and the sensor sends a low-voltage signal. Increase in tension happens at mix impoverishment when the amount of oxygen in exhaust gases increases. Maximum efficiency of full and correct combustion of fuel occurs if the mix "air-fuel" given to the engine is supported in chemically correct relation for full combustion of gasoline – 14,7 weight parts of air to 1 part of fuel (the "stoichiometric" relation). The output tension of the sensor changes in a big interval in this point, ECU uses changes of a signal and corrects the mix "air-fuel" given to the engine, changing width of an impulse of a fuel nozzle (an interval of time when the injector is open).