NTK (NGK) Exhaust Gas Temperature (EGT) Sensor (97865) - Single. This NGK Exhaust Gas Temperature Sensor (RTA9000-EE077 - 97865) is supplied in OE matching quality. Exhaust gas temperature (EGT) sensors are vital for safely monitoring the temperature of the exhaust gas, ensuring exhaust gas cleaning components provide optimal conversion rates for healthier emissions and better performance.