With this higher fuel pressure thru the injectors, will this reduce the amount of carbon build up in the engine? and cause a longer engine life?
The reason for the higher pressures along with multiple injections per cycle is to have a more complete combustion process. When the engine is running correctly there will be a reduction in engine carbon build up. Having said that, new lower emission requirements drove many of the changes to today's engines. Engines need to run cleaner to meet emissions requirements. The EPA mandated reductions in particulate and nitrogen oxide (NOx) emissions have been in the works for over 10 years and have followed a tiered approach. The first tier was Tier 1, which established the first significant reduction in particulates and NOx emissions. The final tier is Tier 4, which has already been implemented for on road heavy duty diesel engines, will have very low emissions, almost to the point where the exhaust gases from these engines will be virtually as clean as the air going into them.
Although the goal was to achieve significantly lower particulate emissions, through a better and more complete combustion process, the benefits are that engine performance keeps improving. Engine technology and efficiencies have improved from one generation to the next and there is every reason to believe that new generation engines will last longer and perform better than previous generations of engines.