P0131 (front 02 sensor low) code

[838]

09 FLHX. New 117" build is running amazing. Just finished 500 miles yesterday.

Before we left the bike had this P0131 code, it's running fine, no check engine light, so I unplugged and plugged back in the sensor (not from the pipe), cleared the code, rode about 50 miles, checked it again and it was not there.

After our 500 mile run yesterday (again bike is running great, no check engine light) and the code is back.

These sensors have been installed on 3 different head pipes so my first step is to run to the closet HD and hope they have an 18mm narrow band sensor.

I've read that this code could come up for other reasons. Should I try anything else besides buying the new sensor. Remember I'm on the road..

[chaos901]

FWIW:  Reading about this code it sounds like it might be a "historic" code since the Check Engine Light is not on.  What causes the code to originate often is simply a loose exhaust connection, possibly from the engine work (guessing).  Historic codes stay in the system for something like 50 cycles before they are erased.

[Pirsch Fire Wagon]

There is a TSB which addresses this. Apparently a "Dirty Ground" (ground other than the Battery (-)) could be the culprit causing the code to appear without the lamp indicator.

[838]

There is a TSB which addresses this. Apparently a "Dirty Ground" (ground other than the Battery (-)) could be the culprit causing the code to appear without the lamp indicator.

Ok, thanks.

Where would/could this be located? if this is the case.

[Coyote]

How was this build tuned?

[838]

How was this build tuned?

TTS on a dyno.

[Coyote]

As I understand that code, it's thrown when the bike is in CL and can't maintain afr. In this case it's lean. Assuming no hardware issues, I would think this is a tuning issue.

[BVHOG]

Your local Independent shop can get those from Drag specialties as well boxed by feuling. Pretty fragile wiring, possibly losing connection either at the plug or sensor could give you the low code

[838]

Replaced the sensor. Bike runs great. No code return after about 10 short rides over 5 days! Cruising rage is smooth and roll ons are way more responsive!

[838]

I replaced the front o2 sensor after getting a p0131 code, cleared the code and rode the bike for a week (checking to see if the code would come back after each ride). It took a while, but it finally popped back up after 25 cycles (over a week... give or take).

What should my next check(s) be? I want to cover all my (other potential) bases before I haul it back 5hrs to my tuner.

I have attached a picture of the condition of the first sensor that I replaced. It had a white ashy substance on the sensor itself and on the nut portion as well..

Thanks