Exhaust gas recirc Volvo 240 (B20F)

Sooty passages and a rough idle can point to the exhaust gas recirculation on a B20F-equipped Volvo 240 clogging up or leaking at a worn seal. The recirculation feeds some exhaust gas back to the intake to lower the combustion temperature, and small leaks in pipes or joints are a common checkpoint during troubleshooting.