what is egr sytem what does it do and what will happen with it removed

Exhaust Gas Recirculation

 

it recirculates exhaust gases whilest the car is on the warm up cycle to help with emissions. its aload of brass pipes into the inlet manifold and a charcoal box and some valves

 

not a great deal really - some people find it annoying, it can go wrong and cause air leaks and the pipes do partially block the exhaust manifold causing gas disruption