This Discovery 3 owner also asked JGS4X4 to perform an EGR delete via the software to prevent any troublesome and expensive EGR problems in the future. This basically disables the EGR valve from operating via the software to prevent any problems before they occur.
A bit of background on the EGR System
The purpose of the EGR system is to reduce nitrogen oxide emissions which contribute to air pollution at certain engine speeds and temperatures. The downside is a reduction in performance and economy and the carbon build up with higher mileage vehicles. With the introduction of the EGR valve system on diesel engines, there has been a noticeable and documented 3% drop in engine efficiency, which means an additional 3% more diesel is being consumed and burned to generate the same amount of power.
Exhaust Gas Recirculation works by recirculating a portion of an engine’s exhaust gas back into the clean air inlet side of engine cylinders. This dilutes the oxygen in the incoming air stream.