O2 sensors

ChevroletTough · February 5, 2020

Hey guys, so I only have 2 oxygen sensors from what I can tell. Both are on the y pipe just below the manifolds. I would assume these are both upstream sensors? I have a p0134 for a bank 1 sensor 1 no circuit activity. I already replaced the passenger side. This appears to be the driver side one. Truck has no cats... so no downstream sensors.

Ac Delco 213-941

Side note: I replaced the o-ring on the oil filter adapter that was leaking, no more leak!

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CamGTP · February 5, 2020

Check for fuses first, then for power at the connector.

If that is good, it may just be a bad sensor.

davester · February 6, 2020

maybe swap the sensors from side to side and see if the problem moves with it?

ChevroletTough · February 6, 2020

The truck is older (2000) so ill probably opt to just replace the other sensor. That way they are both new.

Parts site (ac delco) show 2 upstream and 2 downstream. Hilarious as I only have 2 total.

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Racindave · February 6, 2020

I’ve gotten bad sensors at advance auto a few times..... I don’t buy electrical items from them anymore because of it....

ChevroletTough · February 6, 2020

I order all my AC Delco parts from amazon truth be told, they have the best prices pretty much every time.

I will unplug my new sensor and check my readouts on my bluetooth scanner (realtime).

But the code says B1S1, which would be drivers side. The one replaced was the passenger side as that was the code last time.

davester · February 6, 2020

6 hours ago, ChevroletTough said:

The truck is older (2000) so ill probably opt to just replace the other sensor. That way they are both new.

Parts site (ac delco) show 2 upstream and 2 downstream. Hilarious as I only have 2 total.

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Well, your truck didn't come that way from the factory. Somebody cut off the cat's, removed the downstream sensors and likely had the truck reprogrammed so it wouldn't throw codes because of the missing sensors.

ChevroletTough · February 7, 2020

Truck has a new ECU now so maybe that’s why it’s throwing the code because it only has 2
Of the 4 sensors.

I think they sell dummy plugs to trick the ECU.

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davester · February 7, 2020

You didn't mention the ECU was just replaced. Did you get it programmed for your VIN?

ChevroletTough · February 7, 2020

I did not mention that, lol. And yes, fully programmed with my vin. I had to do the security bypass. Flashmasters.com

If you recall from my other thread, they stated the ECU was bad, when it was in fact the speed sensor tab that was bent. Glad that fiasco is over.

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