An exhaust gas diagnosis system and a vehicle control system for automotive vehicles to reduce the communication lines and the power lines connected to the antiweatherability-required exhaust gas sensor arranged on the exterior of the vehicle are disclosed. The exhaust gas diagnosis system is configured of an engine control unit (electronic control unit), radio terminal units having the sensor function to detect the exhaust gas, and a radio communication repeater to conduct communication and share a part of the process executed by the conventional engine control unit. The communication lines between the sensor and the electronic control unit and the power lines to the sensor required in the conventional systems are eliminated while at the same time reducing the load on the electronic control unit.