CEL code P2251 Rear Air/Fuel Ratio (A/F) Sensor (Bank 1, Sensor 1) VS Line High Voltage. There are 4 o2 sensors on this vehicle; 2 in the front and 2 in the rear. With this code which of the o2 sensors needs to be replaced the rear upstream or downstream?
Jul 21, 2010 at 1:18 PM
