Steve takes a look at Exhaust Gas Recirculation Coolers.  Exhaust Gas Recirculation Coolers and valve or EGR for short has become a dreaded talking point for diesel car owners in recent years, so what are they, how do they go wrong, and how can you prevent your EGR from failing.   What is an EGR Cooler?  It's purpose is to cool the exhaust gasses by passing it through cool air similar to a radiator. After being cooled the exhaust gasses a recirculated to the engine to cool t