Down pipe replacement on a 2014 Fiesta ST =PITA!!! SOOO, I replaced my stock downpipe with the 2JR catless downpipe. The heat shield was a pain, because the up stream O2 sensor would not loosen...and when I finally cam loose, it was bent and is not warming up now. So I am waiting for an O2 sensor from Ford. Also, one of the bolts that connected the flange to the turbo was stripped from factory. I did get it back together and everything seems connected fine. The air fuel is locked at 14.70 and the o2 bank 1 not warming up cel is on. I won't be driving it until I get my new sensor:-(