Performance Products has diesel injection punps? They've referred folks to us for injection pumps in the past...Performance Products, one of our sponsors here, can provide you with a rebuilt one if indeed that is what the problem is. A new one is in the $1,200 range, a bit pricey. You can go to their site and look at the price for a rebuilt one. Eliminate the other possibilities first. A stopped up fuel filter(s) could cause a loss of power too. Have you changed all the fuel filters?