I have a 2003 dakota 4x4 with a 3.9. I can start it up and will run fine for about 1 to 2 miles and then it will start backfiring and losing power until I floor it and then it will run fine but still has the lost of power. It does every time I drive it. I have changed the map sensor, the pick up coil, plugs, wires, cap, and the rotor button. It has also throw the code of po132 which is high voltage short to bank 1 o2 sensor but the check engine light will go off on its own. It does not always throw this code when it acts up. Which one is bank 1 and can this be the problem?

 

I have an 3.9 as well and the o2 sensor was my problem.

Search the thread titled "backfire from hell" for a video showing the problem.

Bank 1 is the driver side cat. Its probably sensor 1 which is the upstream one which is before the cat.

 

Thank you I will try this