Changed o2 sensors now running rough, surging

[Todd L]

I had bad o2 sensors code on check engine light on a off the past few weeks. Decided I would just change all 4. As soon a I switched them out truck went into engine power educed mode. I unplugged battery reset the computer. That allowed it to start up fine but engine light came back on still showing codes for sensors running too lean and the max air flow sensor is now popping up.  Truck surges when driving barely want to go over 30mph. When I'm in idle or at a stop truck is rumbling rpm slightly bouncing up and down. Any ideas on a quick fix to this.

[Mike GMC]

You didn't touch the elements on the O2 sensors as you installed them did you?  Dirt, grease or oils from your fingers can destroy the new sensors.

[CamGTP]

Check the fuses for the o2 sensor circuits and if you have a live data scan tool, that would let you see which sensors is acting up.

[txab]

Where did you buy them and what brand? Lot of counterfeit crap being sold on  Ebay and Amazon. Re-check your connections

[Todd L]

No didn't touch them. Took caps off right before screwing them in. I got them online from carparts.com brand was drivewire.

[CamGTP]

I'd only use Denso/delco sensors in these truck. Maybe an NGK if that was I all I could get.

 

New OEM sensors aren't very expensive and are going to be better than some $20 sensor.

[DMB]

Changed convertors and o2’s now run like crap. Limp mode, rpm’s bouncing, no power. Put old o2’s back in no change. 2020 Silverado 5.3l

[CamGTP]

Why did you change the cat converters and o2 sensors?

 

What codes it is throwing to cause the limp mode?

[DMB]

P0420 showed up after the engine had a lifter repaired. Friend brought it to me to change cat. And o2 sensors. Shop told him bad convertor so I changed them , ran fine when I got it just had engine light 

[CamGTP]

Okay, the new converters could usually fix the P0420.

 

But if after you replace those and the o2 sensors but it's still going into limp mode, there must be more codes that it's throwing to cause that now. That's what you need to figure out.

[DMB]

P0137 bank one sensor two low-voltage. P0172 fuel trim system rich bank one. P0300 engine misfire detected.

Edited February 15, 2025 by DMB

[CamGTP]

Well the obvious would be to make sure that bank 1 sensor 2 is still plugged in. That code could cause the rich code and the misfire.

[asilverblazer]

Were the converters weld in or replace the whole y-pipe? Brand? O2 Sensors brand?

New sensors (parts) does not equal good Sensors (parts). 

 

As an easy check swap the two upstream sensors side to side and see if the 'lean' bank swaps sides too.