99 Sub 1500 4x4 bit rough on accel

[fingerzmcs]

I have a 99 Suburban 1500 4x4 gas with just over 117,000 km's on it. It's given me the same code 3 times now as I've cleared it to see if it keeps coming back. The vehicle seems to run find although while idle you can feel a little miss so to speak. During travel all seems normal but while under load or heavy acceleration theres seems to be a lack of power and maybe like the motor is missing on 1 cyl a bit. Seems like there is a bit of vibration. Here is what the scan pulled Should I change the sensor or could something else be causing this problem an setting off the sensor!

Vehicle Year: 1999
Vehicle Make: GMC
Vehicle Model: Suburbon
Vehicle Engine Size: v8
Stored:
P0161 O2 Heater Circuit (Bank 2, Sensor 2)

Pending:
P0161 O2 Heater Circuit (Bank 2, Sensor 2)
MIL ON
MisFire Monitor Complete
Fuel System Monitor Complete
Comprehensive Component Monitor Complete
Catalyst Monitor Complete
Heated Catalyst Monitor Not Supported
Evaporative System Monitor Not Complete
Secondary Air System Monitor Not Supported
A/C System Refrigerant Monitor Not Supported
Oxygen Sensor Monitor Complete
Oxygen Sensor Heater Monitor Complete
EGR System Monitor Complete
DTC for which Freeze Frame was Stored P0161
Fuel System 1 Status Open Loop
Fuel System 2 Status Open Loop
Calculated LOAD Value 7.45 %
Engine Coolant Temp 73.40 °F
Short Term Fuel Trim - Bank 1 -1.56 %
Long Term Fuel Trim - Bank 1 0.00 %
Short Term Fuel Trim - Bank 2 -1.56 %
Long Term Fuel Trim - Bank 2 0.00 %
Intake Manifold Absolute Pressure 10.63 inHg
Engine RPM 1059 rpm
Vehicle Speed Sensor 4.97 mph
Air Flow Rate Mass Air Flow Sensor 2.16 lb/min
Absolute Throttle Position 1.96 %

[chuck's]

The heater cuircut for the O2 sensor appears to have failed or is not responding properly.The sensor has a heater so the sensor will warm up faster to put the engine into closed loop.This sensor is used to monitor the converter prefomance.I would get the heater circuit monitored with a scan tool and check for the voltage changes.As the heater warms up,the voltage should drop.Monitor all four O2 sensors.You may need to change more than one.You must also check the wiring to the sensor.A wire for the heater curcuit may have broke or has corrosion.
chuck's