Thread: 2004 GTP Comp G .... P0136 and P0137 codes

P0136 = O2 circuit [Bank1, sensor 2]
P0137 = O2 circuit low voltage [Bank1, sensor2]

For the P0137 code, my scanner had….
Fuel Sys 1 CL
Calc LOAD(%) 7.8
ECT(F) 194
STFT B1 (%) 0
LTFT B1 (%) -25.0

I replaced the downstream (under car) O2 sensor with a genuine, new AC Delco part about 2 years ago after I was getting the P0137 code. A few months ago I started getting P0136 and P0137 codes. Could that sensor have gone bad that fast ? I have been clearing the codes in hopes that the long highway drives I have been doing would clear things up. Fat Chance !! Any ideas on how to troubleshoot what’s going on or should I just buy another sensor and put it in…. I don’t recall ever changing the upstream sensor. Could that have anything to do with it ? Thanks…

Same, check fuses and wires, and be sure to put some di-electric grease inside the plug when you're re-connecting the harness.

Alternate option would be to put an extension before the sensor to reduce the chance of fouling. ZZP and many other place have them.
LINK - O2 Bung Extender – ZZPerformance

Thanks guys. I will check all the wiring and the plug at the O2 sensor. I will use some Di-electric grease on it too.
I'll chek back in after I do those things, but it may be awhile with this damn Chinese Virus bs going on.....
What a nightmare scenario for all of us..... I am hoping it's more media hyoe than reality for 90% of the country and world !