Disabling EGR valves?
Several companies advertise products that modify diesel cars to disable the EGR valve. This is acheived either by means of a software update or a blanking plate. In the case of the latter, I believe there is a small orifice to pass just enough gas to prevent engine error messages.
The idea being to prevent the EGR from sooting up and causing running issues as the car ages. In some cases, a performance improvement is also promised.
Obviously this modification is going to affect the emissions of the engine, in particular NOx. Would a diesel modified in this way pass an MOT? Also, seeing as the purpose of exhaust gas recirculation is to lower cylinder temperatures, does disabling the EGR put the rest of the engine (turbo in particular) at greater risk of thermal stress or breakdown?
Would you recommend this as a method of preventative maintenance on a modern diesel?
The idea being to prevent the EGR from sooting up and causing running issues as the car ages. In some cases, a performance improvement is also promised.
Obviously this modification is going to affect the emissions of the engine, in particular NOx. Would a diesel modified in this way pass an MOT? Also, seeing as the purpose of exhaust gas recirculation is to lower cylinder temperatures, does disabling the EGR put the rest of the engine (turbo in particular) at greater risk of thermal stress or breakdown?
Would you recommend this as a method of preventative maintenance on a modern diesel?
Asked on 14 July 2013 by likerocks
Answered by
Alan Ross
There has and will be much said about the EGR, given that I had a modern car that is fitted with a EGR then I would leave it fitted and, as and when necessary, have it cleaned or replaced.
The engine was designed to have an EGR and therefore I would not suggest removing it.
The engine was designed to have an EGR and therefore I would not suggest removing it.
Tags:
egr valves
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