O2 sensor programming?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
19,582
Reaction score
26,269
Location
Treasure Coast, Florida
did you find this on the tech2?
No, AllDataDIY shop manual.
Operation
HO2 sensor is supplied 450mv reference from PCM.
For proper operation, HO2 sensor should be over 600°F.
HO2 sensor generates a voltage dependent on the amount of oxygen present in exhaust.
Rich exhaust results in high HO2 voltage (above 450mv), lean exhaust results in low HO2 voltage
(below 450mv)
IGN(+) is supplied to heater which is built into HO2 sensor.
When replacing the HO2, sensor perform the following:
Clear codes with a scan tool, regardless of whether or not a DTC is set. This causes PCM to perform a
HO2S heater resistance learn reset.




huh. learn something new everyday.
AllDataDIY shop manual says it a little differently:

1718369159687.png
 

j91z28d1

Full Access Member
Joined
Feb 28, 2022
Posts
3,078
Reaction score
3,802
I was doing a idle relearn after cleaning the tb today for the first time and I did see a o2 heater reset below idle relearn on the tech 2.


I feel like aldata and prodamand are owned by the same company? weird they would say it differently. either way, good to know.
 

Charlie207

Full Access Member
Joined
Apr 13, 2021
Posts
1,655
Reaction score
3,294
Location
LFOD, New Hampshire
P0171 is for the left bank (Bank 1); there is a different code for Bank 2.

It can be a bit difficult but if your scanner doesn't graph, you should be able to watch the voltage fluctuate on the upstream sensors. They should oscillate from 0.1 to 0.9v. If the voltage is consistently somewhat below 0.450v then that indicates lean.

If it operates outside of the 0.1v - 0.9v range would that indicate a faulty O2 sensor?
 

strutaeng

Full Access Member
Joined
Aug 10, 2023
Posts
1,178
Reaction score
2,444
Location
Dallas, Texas
If it operates outside of the 0.1v - 0.9v range would that indicate a faulty O2 sensor?
Yeah. But it could also be a legitimately running lean or rich engine, or even a shorted out wiring harness...

You perform a simple test by inducing a rich or lean condition internally and then watching for O2 waveform response.
 

j91z28d1

Full Access Member
Joined
Feb 28, 2022
Posts
3,078
Reaction score
3,802
If it operates outside of the 0.1v - 0.9v range would that indicate a faulty O2 sensor?


outside how? a narrow band o2 sensor is only designed to produce 1v. if it makes more than that, something might be shorted somewhere?
 
Joined
Apr 11, 2018
Posts
7,124
Reaction score
14,364
Location
St. Louis
I've said it before and I'll say it again, aftermarket sensors do not play nice with the computers on these trucks. Especially O2 sensors. This even includes Denso sensors that are NOT in a GM/ACDelco wrapper.

There is a HO2S heater resistance learn reset that can be done. I didn't even know about this until recently and my new sensors have 32K miles on them now.
What are the GM/ACDelco upstream sensor part numbers?
 
Joined
Apr 11, 2018
Posts
7,124
Reaction score
14,364
Location
St. Louis
12583804​
Heated Oxygen Sensor​
Is there a difference between that part # and 2133866?

Some places show the 2133866 as ACDelco and list the 12583804 as an alternative part #

Are they both the same and one is just a newer number?

I've heard non OE sensors have issues with calculating correct alcohol % on flex vehicles. Would either of these part #s work correctly, or one better then the other, or does it matter?
 
OP
OP
B

blondie70

Full Access Member
Joined
Nov 21, 2023
Posts
257
Reaction score
399
I can't answer your questions. The part # I gave is the part # the GM parts place listed on my receipt . I have not gotten the parts in the mail yet. Today, took the Denso sensors out. The left one (the one throwing the code) was black and sooty. The other one was nice and clean. This means something, but I know not what !
 
Top