Hey guys,

I have a 2011 sportster fourty eight w SE heavy breather and Vance and Hines pipes. About a year ago I upgraded cams (Andrews cams w a .490 lift). I have the pro sert and have tuned everything accordingly.
Here's the issue, a few weeks ago the bike started backfiring and bogging down/losing power at around 2900-4200 rpms in any gear.
The sert showed that the front O2 sensor was low voltage/running lean (code # po131) so I replaced the sensor, code is gone but the problem is not. I have tried multiple setups and maps to fix the issue but nothing seems to work.
Any help would be appreciated guys. Thanks!

 

check your battery connections and the frame ground

check the exhaust make sure is tight / torqued

check for intake leak

thats about all i can think of right now

 

Check your fuel pressure. Low fuel pressure will set a lean code and loss of power.

 

air filter dirty?? also check in the intake area for buildup of oil blowby , put you finger in and lift the slide (it should lift pretty easy) ...if you find the intake to be gunked up, give it a good spray with CRC Powerlube, I mean a real good spray, enough so that the stuff is running out all over the place (put rags down first) and work the slide with you finger at the same time...don't use brakekleen or carb. cleaner as they are bad for the elect. sensors and plastic stuff...if that doesn't help, the next step is the fule filtering system...