Peugeot boxer without power, does not accelerate well

Please I wish you can help me with a problem, I have a 2.0 2003 boxer, HDI, have a starting problem, excess of return by an injury, repair it, but the problem is that now they do not have the same strength, the slopes or straight, it takes a lot to take speed in the line



They have constant flickering, as the voltage goes up and low

The EGR is the main cause of these problems in Peugeot you must linked it, it is a factor that causes that symptom not the only one but it is what generally fails, liniandola test and you warn how it goes.

Thanks for the prompt response, but I could tell me how the technique would be to clean it or wash this EGR valve,
I hope you can guide me