I understand that this has to do with O2 sensors. Which 02 sensor is it referring to on my 2004 Ford Escape V6? Is cylinder #1 on the front or rear of the motor and which catalytic converter is it after - the first in the engine bay or the second under the car?

Thanks!

 

It is the one downstream from the converter. The code doesn't always mean the sensor is bad. P0036 means there is an issue with the heater circuit for the sensor. There should be 12 volts sent to the heating element of the sensor coming from the fuse block. That's what I would check first.I would look closely at the sensor's wiring to make sure that it has not rubbed on anything or melted from touching hot exhaust, shorting out the circuit.An open heater element within the O2 sensor is also a possibilty.

 

Yes, I recently had simular issue po136 bank 1 sensor 2 & if u read scan tool it does say (circuit). I tried everything but didnt think 2 check circuit wiring! Low & behold what did I find, the 4 wires had melted in harness in three spots after connector on top of motor that runs down 2 alt & in plastic housing between motor & firewall up to ECM. Repaired wiring & so far so good, no DTC codes. I had went to wrecking yard 4 a harness & found that 5 escapes 2001-2009 had all the same issues w/harness, all had 4 burnt wires to 02 sensor