P0161 code gone bad!!!!
Thread Starter
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Joined: Feb 2009
Posts: 67
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From: DC/MD/VA/DE
P0161 code gone bad!!!!
My O2 sensor finally comes in the mail and I think I got it on the car faster than I got it outta the box j/k lol, but seriously, it wasn't a hard install and all seemed to be fine, cleared the CEL and put a smile on my face 
....until about 30 miles later 
, the frikkin light came back on!!!!
, so now I'm curious??, what else could be the problem??
....until about 30 miles later , the frikkin light came back on!!!!, so now I'm curious??, what else could be the problem??
Pole Position
Joined: May 2007
Posts: 3,405
Likes: 55
From: 408 NOR CAL
Are you sure there are no other codes in the system?
P0161 will come up when the heater current for B2S2 O2 Sensor is over 2 amps OR under 0.2 amps while in operation.
It could be the O2 Sensor or the O2 Sensor circuit (wiring).
P0161 will come up when the heater current for B2S2 O2 Sensor is over 2 amps OR under 0.2 amps while in operation.
It could be the O2 Sensor or the O2 Sensor circuit (wiring).
Thread Starter
Rookie
Joined: Feb 2009
Posts: 67
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From: DC/MD/VA/DE
Im sure, thats the only code, is there any way I can the sensor tested?? or could the fuse for the OBD be going bad (this was recommended by the receipt from the CEL read) but I figured if the OBD fuse (on board diagnosis) was out, the CEL wouldnt have come back on because the OBD wouldnt have caught it again....could this be true??
Pole Position
Joined: May 2007
Posts: 3,405
Likes: 55
From: 408 NOR CAL
If there is a OBD fuse and it is out your scan tool would not communicate with the vehicle. O2 Sensors can definitely be tested. As with all repair information I provide USE IT AT YOUR OWN RISK.
B+ to HT - Resistance should be 11-17 ohms.
B+ to Ground:
KOEO - should read the battery voltage
KOER - should read the system charging voltage
HT to Ground
KOEO - should read the battery voltage
KOER - should read around 0 volts when turned on by ECM (If not possible bad wiring to ECM). It also could read between 0 and charging voltage if the ECM has it in Duity Cycle Control.
FYI:
KOEO =Key On Engine Off
KOER = Key On Engine Running
B+ to HT - Resistance should be 11-17 ohms.
B+ to Ground:
KOEO - should read the battery voltage
KOER - should read the system charging voltage
HT to Ground
KOEO - should read the battery voltage
KOER - should read around 0 volts when turned on by ECM (If not possible bad wiring to ECM). It also could read between 0 and charging voltage if the ECM has it in Duity Cycle Control.
FYI:
KOEO =Key On Engine Off
KOER = Key On Engine Running
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Pole Position
Joined: May 2007
Posts: 3,405
Likes: 55
From: 408 NOR CAL
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Thread Starter
Rookie
Joined: Feb 2009
Posts: 67
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From: DC/MD/VA/DE
P0161 was the only code, the original O2 sensor in bank 2 was bad. Due to the replacement, its showing the new code because its getting readings from that area. Please know the whole story before being a douche
Pole Position
Joined: May 2007
Posts: 3,405
Likes: 55
From: 408 NOR CAL
The "whole story" to people on this forum is only what you tell us. I asked "Are you sure there are no other codes in the system?" to which you replied "im sure, thats the only code" and then later, presumably after actually checking the codes, replied "the new CEL is because of a p0420..."
I tried to help you, you appeared to have assumed there were no other codes, and now I'm a douche. Riiiiiight.
I don't hold grudges but I do remember which people are appreciative and which are not. Even though you did not feel the need to thank the only person beside GS300ToM to reply to your request for help including information on how to test your O2, and actually called that person (me) a douche, I will say Your Welcome.
