Brian,

While I know you are excited about the very short-term results you have seen, it would be prudent to wait for a much longer period of time before prescribing this as a fix.

Personally, I am not optimistic that you have fixed anything and that the symptoms are most likely to appear in short order.

Here is a Ford TSB that is intended to provided guidance to dealership technicians in diagnosing concerns with HO2 sensors and cats: http://www.thedieselstop.com/faq/9497faq/tsb/tsb/files/010907.pdf

Pay particular attention to the section on pages 8-10 that describe how the cat efficiency monotoring works. If your scan tool is capable of displaying the front vs. rear O2 sensor outputs, you will be able to see what effect the cat is having on the oxygen level in the exhaust. With this real-time data, you will be able to see the actual performace of the cat and will be able to see if the performance is changing as you drive the car a few more miles.

Again, I would urge caution and more time before trying this on another car with 0420/0430 codes.

Steve

98 Contour SE Sport 2.5 Duratec ATX The wifey's car 89 Taurus SHO - 246K miles 94 SHO ATX - 190K 1997 F-150 5.4L ATX - The Workhorse 150K. ANY THREAD WITH "OMG" or "WTF" ETC IN THE TITLE WILL BE IGNORED!