1994 Mercedes-Benz S420 EGR Valve Replacement Cost

An illuminated check engine light could lead to a fault code indicating a problem with the Exhaust gas recirculation (EGR) valve. In this case, the manufacturer suggested diagnostic procedures should be followed to isolate the cause. Removal of the valve may be required for a visual and functional inspections.

Once the valve is located and made accessible (on some models this can be very easy and on others it can be quite a challenge), relacement commonly involves unbolting the old valve and installing the new one. Rust can develop on the mounting nuts/bolts so penetrating oil should be used prior to attempting removal. Care should be taken around hot exhaust components. While the valve is off, it is a good time to check the be sure the EGR passages are clear.

Always take care when working around hot exhaust system components and use penetrating oil before removing rusty nuts/bolts. EGR passages should be inspected while the valve is of to be sure they are clear of carbon buildup. When replacing the EGR valve, Vacuum hoses and or electrical connectors attached to it should be inspected and repaired or replaced as necessary.

Care should be taken when working around hot exhaust system components. EGR passages should be checked for carbon deposits whenever possible and cleaned as necessary during valve replacement. Rust can develop on mounting nuts/bolts, penetrating should be used prior to removal.

The location of the EGR valve will most likely to determine if the is a DIY project or not. In some cases removal of additional components will be necessary to gain access to the valve, for testing as well as replacement. You will need to determine if you are up to the task or not. Certain models may also require special tools to remove nuts/bolts securing the valve.