the O2 sensor is on that would be throwing this code.

P0136 - HO2S Sensor Circuit Malfunction (HO2S-12) The downstream HO2S sensor(s) are continuously checked for maximum and minimum voltages. The test fails when the voltages fail to meet the calibrated limits. Pinched, shorted, and corroded wiring and pins.
Crossed sensor wires.
Exhaust leaks.
Contaminated or damaged sensor.

The wiring looks good so I want to replace the sensor. Where is the best place to buy it also? Thanks is advance

 

I got a pair of 'em from Kragan at a decent price. When they first started being used on cars, they needed replacement at about 50,000 miles, but they now go at least 100,000. They don't usually just quit, but instead their response time slows down and the engine does not run as well as it should.

 

If you have headers make sure you check the harness extention, in the end that's what caused all my probs....

My Code book list it as:
P0136 O2 Sensor Circuit Malfuntion (Bank 1 Sensor 2)

 

I dont have headers but I have a Bassani catback. I looked at the harnesses and they seem fine.

 

Bank 1 is the passenger side.

 

Hey thanks! Does it have to be a Motorcraft one? My bud at the auto parts store says he only sells Standard Ignition brand. The SI brand is like 40.00 and the part at the Ford dealer is 112.50.

Which one would you get?

 

Go for the cheaper one. We all know stealerships are way overpriced.

 

hi Rob_02Lightning I have headers and got a 138 code how did you fix your problem can u get a new harness extention
did you just test with a ohm meter how did you find this problem

 

Since, this is back at the top, I'll update that I changed the sensor and it solved the problem. Thanks.