My Suzuki Boulevard C50T is throwing the c23 factory code I changed the bank angle sensor what else could it be

SOURCE: Mobil 1 LS 75w-90 synth gear oil for final gear oil replacement?

use EP80 or EP90 gear oil only,,,,

SOURCE: Check engine light (emission system service required) Help?!?!

There may be problem with the mass air flow sensor (very common with Volvo). This causes the fuel system to malfunction.

You may have noticed increased fuel consumption, loss of power and general 'lazyness'.

Better to take it to authorized Volvo service for a checkup/fix.

SOURCE: codes

Your sensors are reading correctly so leave them alone. What you have is a fuel delivery issue. Your MAF sensor is telling your engine to lean your fuel mixture. You need to remove and clean or replace (is better) the MAF. But first replace your PVC valve and clean your ERG valve.

SOURCE: how to change a fuel bank sensor #1 code p1135 on

P1135 Air/Fuel Sensor Heater Circuit Response. (Bank 1 Sensor 1) ask any auto parts store what the fix is.

SOURCE: 2002 chevy silverado hd2500 6.0 ecm code po332 low

If all connections are good "dry, tight, no corrosion" then yes. It should be a defective sensor. These sensors are piezo sensors and create a voltage when sensing a knock. A bank refers to a side on a V style engine, 2 refers to the rear sensor on your bank 2. Bank 1 should be the side with cylinder #1 which should be the cylinder closest to you on one of the sides. So your looking for the rear sensor on the opposite side.