Ford Excursion, Expedition, Lincoln Navigator 2000-2005

Exhaust Backpressure Regulator



The exhaust back pressure regulator (EPR) is a variable position valve that control the exhaust back pressure during cold ambient temperatures to decrease the amount of time required to bring the engine to normal operating temperature. The PCM measures the exhaust back pressure, ambient air temperature, and the engine oil temperature to determine the desired exhaust back pressure.