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Hi guys!
As the title implies, I ran into some troubles with my front cyllinder o2 sensor,
I have a sportster 48 from 2016 stage 1 with vh shortshots, vh air filter and FP4 tune. Recently I had to take the top end off of my front cyllinder to remove a broken exhaust stud.
When I put everything back together and started the bike It fired up just as it always does except now the check engine light was on and there was a faint smell of gasoline.
I checked on the FP4 app and the codes that appeared were P0031 and P0134. I tried clearing the codes but they keep popping up. I also cleared the same codes from the bike's diagnostic mode.
I removed the sensor to inspect and clean it. After reinstalling it and firing the bike now only P0031 appeared.
I also checked the wiring and the pins and everything seems in order.
When I took the top end off I also cleaned the carbon deposits from the cyllinder head. Could there be any afr mismatch between the cyllinders causing the ecm to give this error codes? I don't want to buy a new o2 sensor for nothing.
Thank you!
Perhaps you might try clearing the code, then swap the front O2 sensor with the rear O2 sensor
to see if the code follows the supposedly "bad" sensor (P0051). Just a thought....
Swapping the sensors, what is the recommended method of removing a sensor? Last one I had removed in my auto, guy heated the bung to dull red color ~1200 degrees!
Last edited by hammer6315; Aug 14, 2025 at 07:35 AM.
I have only removed the sensors from the previous iteration which are 18mm not 12mm. I bought a proper socket that has the side removed allowing the wire to stick out.
Now I did this with the header off the bike so I was able to stand it up on the ground and put my weight on the breaker bar that I used.
The Iron 883 that I sold to a friend last month is running rough, after about a mile of riding it is coughing and spluttering, the revs go from slow to fast intermittantly, the engine management light is illuminated. The fault code is P0131, can this be due to a faulty front O2 sensor?
The air filter is a Rough Crafts type and the mufflers are stock H-D, see the image.
Any assistance will be greatly appreciated, thanks.
The motorcycle had been stored and unused for eighteen months.
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O2 Sensor issues
