Ford XL3Z-9D475-CA EGR Valve

The EGR system helps reduce oxides of nitrogen (NOx) by recirculating exhaust gases from exhaust ports through the EGR valve and back into the intake manifold, thereby lowering peak flame temperature during combustion. Models are equipped with the Electronic Exhaust Gas Recirculation (EEGR) system, which depends on the PCM for EGR control. The EGR flow rate is gauged by monitoring the pressure across a fixed orifice when exhaust gases pass through it, termed the Differential Pressure Feedback (DPFE) system. The system consists of the EGR valve, EGR vacuum regulator (EVR), Powertrain Control Module (PCM), differential feedback pressure sensor, EGR pipe, and various vacuum hoses. For EGR valve replacement, use the code stamped on its top when buying a new one. Turn the ignition OFF, remove the air filter housing, disconnect the EGR valve connector and vacuum hose, detach the EGR pipe, and remove the EGR valve retainer bolts. Clean the EGR valve gasket surface if reusing. For EGR pipe replacement, disconnect the vacuum lines from the DPFE sensor and the pipe at the manifold and valve. For the EVR, disconnect the electrical connector, label and detach vacuum hoses, and remove the regulator. For the DPFE sensor, disconnect the electrical connector, label and detach vacuum hoses, and remove the assembly. The 6.4L diesel engine uses two coolers for its EGR system, with the EGR valve located on top of the engine. It fits into a hole in the intake tract, sealed by an O-ring, and is attached with three bolts. Due to its tight fit, a special tool (Ford #303-1267) is required for removal, suggesting dealership involvement for replacements.