New to this

Hello all,first post I have put here but have dipped in and out to get information from time to time.first up brilliant site and loads of information.secondly I need to ask for your help.I have an 04 freelander sport td4.I have read most of threads to do with blanking the egr value.I didn't buy the kit instead decided to go the stingy route.when I blank it all off, and warm up the engine on a drive I will loose power bout 60-70mph.have checked all breather pipes and changed the sensor at the turbo.no difference but when I put the egr value back standard it drives fine with no engine light coming on just not as lively as without the blanked egr.any ideas appreciated.sorry for the long post just wanted to say it all in one go.thanks in advance.