my 2010 fxdc has seemed like it has lost power and gained more vibrations so I did a diagnostic and got a p0154 sensor open/not responding/high i know its for an 02 sensor but is there any way to tell which one? Also the bike has v&h BSS does any one know if they take a stock size 02 sensor?

 

That code should be for the rear sensor. All VH pipes ive run into use the stock size as well.

 

I looked in my Clymer manual for 08-09 it says rear sensor but for 10-11 it doesn't say which one it just says sensor.

 

It is for the rear sensor. Before you buy new sensors you should check the wiring and connections for each one. Since the exhaust has been changed out it's possible that something was damaged or pinched in the process.
Here's a guide for the codes, Clymer is not always accurate for every model.
https://www.fuelmotousa.com/p-29661-...ble-codes.html

 

Thanks I found it a pin was pulled back in the plug.

 

Good job