I'm on my 4th DPFE in less than 3yrs. I tried 2 aftermarkets from Autozone (black plastic type) and they both failed in less than a year. I finally went with Ford part (black plastic) from ebay for more than half the cost of dealer. If this one fails, I have got to look at some other cause. I just checked ebay, and there are a couple available.
http://cgi.ebay.com/Ford-DPFE-sensor...QQcmdZViewItem
I believe that part # f77z9j460ab will work for your '01- check it with the dealer and also check out prices at Rockauto.com and TeamFord parts online. I have had the best luck and prices through ebay, but I would stay away from a used sensor. Good luck.