Where is the location of the bank one sensor one o2 sensor on my 2003 chevy suburban

7/8" Oxygen Sensor Socket or Wrench and one electrical plug. https://www.freeautomechanic.com/ho2s-heated-oxygen-sensor.html

bank 1 is on the rhs block if you are facing the engine
O2 sensors are located after the cat converter/s
HO2S ( heated sensors) are located in the exhaust manifold or before the cat converter
there are differences in the sensors

P1133 indicates heated oxygen sensor insufficient switching bank #1 sensor #1. P0131 indicates voltage from that sensor is staying low more than 2 minutes. That sensor could be bad or it could indicate a rich condition.

there will be an oxygen sensor for both engine banks.

when you go to the parts store this is referred as the down steam o2 sensor. its located under the vehicle on the exhaust left drivers side

Fig. Fig. 3: Oxygen sensor-4.3L engines

Fig. Fig. 4: Oxygen sensor-5.0L and 5.7L engines

Fig. Fig. 5: Oxygen sensor-7.4L engines

Oxygen sensors are always numbered like this:
Bank 1 sensor 1
Bank 2 sensor 1
Bank 1 sensor 2
Bank 2 sensor 2

Some manufacturers use a kind of shorthand that reads different, but means the same thing:
Sensor 1/1 or O2s 1/1
Sensor 2/1 or O2s 2/1
Sensor 1/2 or O2s 1/2
Sensor 2/2 or O2s 2/2

Bank 1 is always the side of the engine where cylinder number 1 is located and, of coarse, Bank 2 is the opposite side.
On a 4 cylinder engine, there is only 1 bank and it is always referred to as Bank 1.

Sensor 1 is always the upstream sensor (the one located BEFORE the catalytic converter)
Sensor 2 is always the downstream sensor (the one that is located AFTER the catalytic converter.

Hope helps (remember to rate this).

Hi, if the suburban is 1996, or newer, you will have 4 O2 sensors. The sensor mounted before the catalytic converter, is sensor 1, and the sensor after the cat, sensor 2. These can also be referred to as pre, or post. The driver, or left side of the engine, is bank 1, as the passenger, or right hand is bank 2. years prior to this, use 1 O2 sensor. Good luck...Coop

Hi, if the suburban is 1996, or newer, you will have 4 O2 sensors. The sensor mounted before the catalytic converter, is sensor 1, and the sensor after the cat, sensor 2. These can also be referred to as pre, or post. The driver, or left side of the engine, is bank 1, as the passenger, or right hand is bank 2. years prior to this, use 1 O2 sensor. Good luck...Coop

bank 1 will be the side with cylinder #1 sensor one will be the first sensor on that pipe

Ther are at leat 3 and maybe 4 o-2 sensors in that particular truck...one on each exaust pipe coming down from manifold...and one after convertor on each bank....Pass.side before convertor is bank one,sensor one ..behind convertor is bank one sensor two..drivers side before convertor is bank two,sensor one...behind convertor is bank two sensor two(If equipped with four....scan will tell you which one is bad....good luck..lee