Weird O2 Issue.


New Member
Jul 18, 2013
Hello all,

I've read for hours about O2 sensors and their problems but this one is a little beyond me:

I have an 06 GT with a BAMA performance 93 octane tune, an off-road X pipe, and a Magnaflow catback (and 3.73 gears and a Steeda CAI if it's relevant). I had slow response codes from the front O2 sensors that kept coming back every hour or two of driving, so I replaced them and all was well for almost 3000 miles and now I have the code back for one of them (I believe it's the one on the manifold). I don't have headers (I have stock manifolds).

I've spoken with mechanics and all, but nobody seems to understand what the issue is or why it seems to be 'eating' O2 sensors, so if anyone can help I'd REALLY appreciate it. Thanks!
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Check the grounds. Poor grounds will cause issues with the O2 heater circuits and result in mysterious slow response times. Also, check for ground side voltage coming from the cooling system due to dirty or contaminated coolant. You would warm up the car, relieve the cooling system pressure and dip the positive lead of your meter in the coolant being careful not to touch the radiator and touch the negative lead to battery negative. You don't want to see any more than a tenth of a volt maximum. I have seen this trip up many a troubleshooter. For instance, let's say you back probed the TPS and read .9 volt at closed throttle. If the cooling system was pushing .5 volt into the ground side circuit, the ECM would only see .4 volts from the sensor. Get it?
ive had this problem and it was because the o2 sensors were not turned off, if they remain on your check engine light will come on every time. if you have a bama turner which i also have you can either order a new tune or use the tuner to re-flash your car using the "strategy" setup and you can select to have the 02's on or off
hope this helps