Best way to test the EGR (exhaust gas recirculation valve) on these cars is with the factory BMW scanner "ISTA". With a capable scanner it is possible to activate the valve for testing purposes and then check the sensor feedback if it is moving correctly. Code P0401 warns of problems with your EGR system, from a faulty valve to a dirty temperature sensor. The severity of the problem varies depending on the extent of the components affected. Total repair costs range from $150 to $750, inclusive of labor and parts. It is important that you pay close attention to your vehicle’s warnings. Check line and plug connections. 2. If wires and plug connections are OK: 3. Check the changeover valve for function with the functional check. 4. Check the coolant temperature after low temperature EGR cooler for plausibility. If the previous checks are OK: Renew changeover valve. Shop OEM BMW EGR Valves at BMW Parts Deal Up to 40% off Now! We offer factory BMW EGR Valves for all BMW series and models. Contact Us : Live Chat or 1-888-580-1680 Many of 2015 X5’s Complaints Covering Engine Problems Point to the Fuel System and EGR Valve as the Causes. One of the biggest problems with the 2015 X5, which prompted one of vehicle’s six recalls and many complaints, is its faulty high-pressure fuel pump. Low Pressure EGR Problem. So the dealer came up with 2 recommendations. Wanted to get your thoughts based on the diagnostics report. I appreciate any direction you guys can give me. Either replacing the EGR myself or the Solenoid. Thanks, Claudio. Attached Images. CLAUDIO.X5-DIAG.pdf (1.80 MB, 653 views) Effectively, it introduces everything you don't want in your engine: 1. increases intake temps by diverting hot exhaust gases (sometimes up to 1400 degrees) into the EGR then the intake - so much for a cold air intake system for a diesel. 2. decreases power by diverting hot exhaust exhaust gases into the intake. 4902 posts · Joined 2010. #2 · Mar 26, 2022. Check the egr actuator under the inlet manifold. BW chiptune. -Tuning BMWs since 1991. -Dyno Dynamics rolling road. BW autorepairs. -Over 30 year repairing BMWs. -New and fully refurbished BMW/Alpina ,Ecus (DME,DDE)and Cas units. jEz5Rl.