I picked my RV back up from the dealer tonight... They claimed they had fixed the problem by replacing the fuel filter. It ran great for about the first 15 miles, but then began to slowly lose power. By the time I made it to my house (50 miles away) it was dying everytime I let off the accelerator. Also, while cruising on the highway, you can feel the power surge about every 15 seconds. The motor will slow waaay down to about 1400rpm's and then it will jump up to about 2200rpms for about 15 seconds, then slow back down... and over and over. I thought maybe I was low on fuel, so I stopped and put 20 gallons of diesel in and the problem presisted... The dealer is very unhelpful, does anyone have any ideas ?