system lean "Bank 1"

[happydog500]

I was driving my car down the road and got a check engine light. I went to auto zone and got a P0171 Code.
They list 4 possibility's, tho he said it usually is the O2 Sensor.

One thing I was wondering about is the code is a "Lean (something) Bank 1". What is this "Bank 1" thing? I remember on another car it said just an O2 Sensor, not a Bank 1.

I could not feel any difference in performance or running, although for a few months every once in a while it doesn't instantly start right up.
Thank you,
Chris.

[stuzman]

Originally Posted by happydog500

I was driving my car down the road and got a check engine light. I went to auto zone and got a P0171 Code.
They list 4 possibility's, tho he said it usually is the O2 Sensor.

One thing I was wondering about is the code is a "Lean (something) Bank 1". What is this "Bank 1" thing? I remember on another car it said just an O2 Sensor, not a Bank 1.

I could not feel any difference in performance or running, although for a few months every once in a while it doesn't instantly start right up.
Thank you,
Chris.

Bank 1 is the bank that has the #1 cylinder. This bank contains #1, 3, 5, and 7 cylinders which is closest to the radiator.

[happydog500]

Originally Posted by stuzman

Bank 1 is the bank that has the #1 cylinder. This bank contains #1, 3, 5, and 7 cylinders which is closest to the radiator.

So what your saying is the O2 Sensor is not working for half the cylinders but it is for for the other half?

[maxwedge]

To continue with this please post year , thanks.

[happydog500]

Thank you, 1997.

[richtazz]

some vehicles use separate o2's to monitor each bank, hence the bank-1, bank-2 code designations. Since generic scan tools cannot read vehicle specific data, that is why it scanned as bank-1. It is basically telling you that your pre-cat o2 is reading lean. This could be from a multitude of reasons, not necessarily meaning the 02 is bad. A vacuum leak, dirty fuel filter, etc... can trip this code.