O2 sensor reading for bank 2 stuck in very narrow range
07-26-2013, 08:13 PM
#1
O2 sensor reading for bank 2 stuck in very narrow range So my TA is running rich so i started monitoring the readings for banks 1 and 2 on my aeroforce scanner. Bank 1 shows normal range between 0-990 mv. Bank 2 however seems to be stuck in the range of 430-460mv or so. I changed both sensors and put 2 new ones in and still getting the same readings. Whats could be going on here?
07-27-2013, 12:45 PM
#3
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If you have one of the O2 sensor faults the PCM
will jam the input to mid-rail, even if wiring is good
and the sensor not totally dead. Check for no-MIL
but still enabled "code killing" if the tune has been
touched. And with the Procharger on there, I would
hope it has.
will jam the input to mid-rail, even if wiring is good
and the sensor not totally dead. Check for no-MIL
but still enabled "code killing" if the tune has been
touched. And with the Procharger on there, I would
hope it has.
07-28-2013, 08:28 AM
#4
I checked all the wiring from the plug to the PCM pins and have continuity on all of the wires. The O2 sensors are new but I didnt clear the engine light after I installed the new O2 sensors, so I am going to try that and see if that fixes the problem.
08-08-2013, 07:02 AM
#6
It actually did work... Temporarily. After I cleared the codes bank 2 voltage was fluctuating normally for about a day. Then, next day it was stuck back in the 430-460mV range. 
I thought that the wiring may possibly be too close to the header, so I zip tied it as far away as possible from the header and also put about a half of roll of heat tape on that one stretch of harness.This thing has got me confused as hell. All the wiring is good. The sensors are new on both sides. But the stock sensors with less than 60k miles did the same thing, so I'm thinking its not the sensor itself on that side. So if the sensor is good, the wiring is good, what else could it possibly be? What is going on???
I thought that the wiring may possibly be too close to the header, so I zip tied it as far away as possible from the header and also put about a half of roll of heat tape on that one stretch of harness.This thing has got me confused as hell. All the wiring is good. The sensors are new on both sides. But the stock sensors with less than 60k miles did the same thing, so I'm thinking its not the sensor itself on that side. So if the sensor is good, the wiring is good, what else could it possibly be? What is going on???
08-08-2013, 07:39 AM
#7
Ok, so i found this very informative technical article about O2 sensors:
http://www.autodiagnosticsandpublish...or-testing.htm
It sounds like it has to be a wiring issue. Either the signal or ground must be faulty or intermitent in my case since it doesnt work most the time, but it has worked for a short amount of time.. Im thinking perhaps the pins in the connector may be a little too loose around the connector of the sensor. Maybe while I was checking the wiring I could have jammed the multimeter lead too far into the connector? I suppose its worth checking. I really hope that is the problem because I know the wires are good going from the connector to the PCM as I took all the loom material off and inspected them when diagnosing it. Even put a new loom on and, as I stated already, new heat tape on top of the loom.. Guess my next step is to inspect the connector. If its not that, I am going to be going insane!
http://www.autodiagnosticsandpublish...or-testing.htm
It sounds like it has to be a wiring issue. Either the signal or ground must be faulty or intermitent in my case since it doesnt work most the time, but it has worked for a short amount of time.. Im thinking perhaps the pins in the connector may be a little too loose around the connector of the sensor. Maybe while I was checking the wiring I could have jammed the multimeter lead too far into the connector? I suppose its worth checking. I really hope that is the problem because I know the wires are good going from the connector to the PCM as I took all the loom material off and inspected them when diagnosing it. Even put a new loom on and, as I stated already, new heat tape on top of the loom.. Guess my next step is to inspect the connector. If its not that, I am going to be going insane!
