Factory909

I am new here, and hate for my first post to be begging for help, but here goes...
I've got an 2008 Tahoe that popped up the CEL back in summer, got it scanned and the codes were for the Bank 1 Sensor 1, Bank 2 Sensor 1 on the O2's. I replaced the driver side with ease, but had to have a shop do the 2nd one (I just couldn't get it). Well here we are a month later and the Bank 2 sensor 1 has popped up again. I can't remember the code exacly, but it was the heated o2 sensor bank 2 sensor 1. I've checked the ohms between the two black leads on the sensor and I am getting around 80 OHMs. Checked it on a good sensor, and it was also around 80OHMS. Could this be a bad sensor? What else can I check? The vehicle is running perfect, no decrease in MPGs that I can tell, no hesitation, no smell.

Fast forward a few days...

Well I pulled the bank 2 sensor 1 out today and put a multimeter on it and took a torch to it. Could NOT get it to register anything. Took it back to autozone and they warrantied it. Got it installed, got the code reset, and so far so good, but I am not 100% convinced its fixed. Only time will tell.

Fast forward a few more days...

The code keeps popping up and going away. Dealer said Tahoe is running perfectly fine, but the code that keeps popping up is P1153. I've Googled until my eyes are bloodshot (maybe the alcohol!). I've narrowed it down to bad connector, or wiring on the harness side. I'm going to put the multimeter on the connector, harness side, and ohm each pin out with the other pins see if I can see if there is a short somewhere. Anyone got any other suggestions? I am not getting any other codes, fuel mileage has not changed, still getting around 15.5-17 in town, nothing changes when the CEL comes on...

It seems like my options are either finally get it fixed, keep resetting the light (I bought a code scanner), or get a tuner to tune out the P1153 code..

Suggestions?

tech2

there was an ecm reprogram released in late 2008 to address this

Factory909

Thats music to my ears, but I can't find any information about it. Do I just take it to the dealer and tell them I want the ECM reflashed to the newest firmware?

in2pro

Factory909 Welcome to the forum...
Rarely will the Dealership take your advice for checking for updates, they will most likely want to do a diagnostic check/evaluation and some of their own troubleshooting before coming to that same conclusion...
But yes it might be best take it in, explain what you have learned and go from there... there may be some cost involved since you have already replaced the original O2 sensor(s) with aftermarket....

Chevrolet Customer Service

Factory909,

Let me know if you would like for me to reach out to your dealership on your behalf. Please private message me your name, VIN, dealership, and phone number.

Erica Tiffany
Chevrolet Customer Care

subfan597

That sounds like the air/fuel sensor (upstream oxygen sensor) problem I had. Find the AF relay in the fuse box and switch it with a similar one, say one for lights. If the check engine light goes off AND the lights don't work its the AF relay. If the check engine light goes off AND the lights still work, switch the relays back to their original location. If the check engine light remains off AND the lights work it was a matter of a loose connection at the AF sensor relay. There is a fuse for this also, I believe, but if that were bad i would think the check engine light would always be on. New relay is about $15.