You wouldn't have to reset anything. How did the car run with the bad valve? Does it run the same as it did before, now that you put the old valve back in? It could be possible you put the valve in wrong, that the valve is also bad, or you got the wrong valve. I don't know much about this specific problem or these valves, so this is about as much help as I can offer... answering these questions, though will help me, and anyone of greater knowledge on the newer escorts to help you find a solution.