Modern engines re-circulate some of their exhaust gases back into the engine with the aim of reducing emissions.

This is the main benefit of the EGR system. The downside is that exhaust fumes containing carbon deposits are constantly being

re-circulated through the engine through time causing a build up of carbon deposits in the in-take manifold etc.

These deposits sometimes contribute to the failure of the EGR system itself.

 

Replacement EGR valves can be expensive and in the case of high mileage engines the continual carbon build up can eventually lead to total engine failure. Removal of the EGR system by blanking off the exhaust input and re-programming of the engine management ECU results in lowered engine temperatures, improved throttle response and economy and also can lengthen engine life by reducing oil contamination and carbon deposits.