Bloody good point Badams I didn't fully explain that one at all ( **** it )
I am afraid the credit must go to Honest John who first reported this following feedback from the trade...
valve should open to allow carbon dioxide, which acts as a cooling gas) into the combustion chambers when the engine is under load (>30% boost). This allows the combustion chamber temperature to drop and thus the temperature of the exhaust gases. If it sticks in the closed position the exhaust gas temperature will rise causing a) the
bearings to fail and b) engine
into the induction system. This will cause the engine to go on running until it has consumed all its
and then it will go bang.Problems with
valves in Renault dCi engines are often the cause of rough running when the valve is stuck in the open position as well. In several cases turbos have blown but the
valve has not been replaced. Inevitably the new
unit will not last long. "