If there is a leak anywhere in the pipe or its fittings, it definately could cause driveability problems for you. If there is a hole in the pipe where it got kinked, you need to replace it and are at the mercy of Ford. If the kink isn't too large and deforming and the metal hasn't fractured, then the pipe should still be good. The next thing is what about the connection where it bolts on to the header? It was a pain to get my egr pipe aligned with the random tech cat and then tighten it enough. If you can't see any holes, wait until the engine is cold, start it up and feel for any kind of a breeze from the egr pipe or its fitting. If it's not below freezing spray some soapy water on the pipe immediately after startup and look for bubbles. That will tell you if there is a gas leak there. This only works for a short time-the header will get hot very quickly.
