Stumped on "No activity" code on both 02 sensors
Thread Starter
Teching In
Joined: Jul 2017
Posts: 23
Likes: 0
Stumped on "No activity" code on both 02 sensors I have a 02 5.3 Tahoe engine in my 71 C10. I have always had a "no activity" codes on the truck since i have had it. Codes is on both sides on my 02 sensors. I just put 2 new sensors in. Before i screwed them in exhaust i connected them to the harness turned on key and the heaters are working on both of them. I just bought a code reader from Summit that reads "live data". I am reading changing voltage on both sensors. The "fuel management" never goes to closed loop.
What else could cause the 02 sensor circuits to not work? I am out of options.
What else could cause the 02 sensor circuits to not work? I am out of options.
TECH Fanatic
Joined: Dec 2017
Posts: 1,469
Likes: 267
From: Bossier City, Louisiana
Who did the programming on the powertrain control module? Did this person delete or otherwise suppress everything related to the oxygen sensors? For my 5.3 liter PCM's, only the two O2 sensors after the catalytic converter are turned off.
Post a copy of your tune and somebody around here can tell you what's really going on.
Rick
Post a copy of your tune and somebody around here can tell you what's really going on.
Rick
Thread Starter
Teching In
Joined: Jul 2017
Posts: 23
Likes: 0
I dont have a copy. I did have a very well known local tuner come out and connect his HP tuner program. He said they were no activity from either of them before i replaced them.
What are the odds it would be a bad ECM?
What are the odds it would be a bad ECM?
TECH Regular
Joined: Dec 2011
Posts: 420
Likes: 115
I would suggest to read up, and verify your O2 grounding setup. Search on Case ground vs Isolated ground. I had issues with my setup at first, and had to run some additional grounds. You need to make sure that your ECU, Harness, and Sensors all have the same grounding strategy.
2002 Engines could be a mix of either type, from my understanding...
http://lt1swap.com/vortec_o2_sensors.htm
2002 Engines could be a mix of either type, from my understanding...
http://lt1swap.com/vortec_o2_sensors.htm
Staging Lane
Joined: Jul 2018
Posts: 76
Likes: 4
When you say you have O2 activity, do they cycle from around 100mV to over 800mV?
They should do that once or twice/second. It's easiest to see if you graph the O2 data, but if you watch digital data you'll be able to spot the low/high averages.
Joe
They should do that once or twice/second. It's easiest to see if you graph the O2 data, but if you watch digital data you'll be able to spot the low/high averages.
Joe
