2001 se and got the codes pulled for two o2 sensors with po158 ,,po134..po135, the po134 and po135 are the same sensor ,does anyone have any idea which sensors need to be replaced,,i know for a fact that there s 4 sensors in the 2001 engine,,if possible ,,, part numbers of those sensors would be helpful so i can order those sensors online,,

 

If you had read the "5th Gen General Information, Maintenance, and Common Issues" sticky, you would have seen this:

http://i6.photobucket.com/albums/y22...nsorsedit9.jpg

Codes P0138 & P0139 are the same sensor, the Bank 1, Sensor 2 (HO2S2-B1)
Code P0155 is the Bank 2 Sensor 2 (HO2S2-B2).

These are also called "downstream" sensors.

Bank 1 sensor 2 = 226A0-4L713
Bank 2 sensor 2 = 226A0-4L715

 

thanks for the helpful information DennisMik