What Does P0476 Mean? The most common cause for a P0476 code has to do with a Faulty Exhaust Back Pressure Valve. Other causes include an open or shorted Exhaust Back Pressure Valve harness or a poor electrical connection in the Exhaust Back Pressure Valve. engine code P0476P0476 fixobd P0476dtc P0476obd code P0476obd2 P0476P0476 car codediagnostic code P0476car code P0476check engine code P0476fehlercode P0476P0476 fiatcodigo P0476codigo falla P0476P0476 kody b??dówcodigo de falla P0476 What are the common causes of P0476 ? In most cases, this code is caused by a clogged back pressure tube and/or exhaust back pressure sensor. However, technicians also report that damaged and burnt electrical wiring and connectors are a possibility. The PCM could also be faulty but this is highly unlikely. How do you troubleshoot P0476 ? With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. Pack the connector cavity with dielectric silicone compound (same stuff they use for light bulb sockets and spark plug wires) and reassemble. Searches related to P0476 - Exhaust Pressure Control Valve 'A' Range/Performance exhaust pressure control valve 7.3 powerstroke location p0476 7.3 powerstroke p0746 p0603 p0456 ford truck forum f350 ford super duty forum diesel talk forums