Original post by: Your ,
The EGR system is built in your engine if it was manufactured after 2002. It was designed to lower NOx emssions but I created a lot of problems; Coughing, black smoke, power derate and surges, and a lot more. What all these devices try to do in different ways is to get rid of all those problems. I tried the one in www.egrxtremepower and it does great, no mechanical problems, more power and better fuel mileage.