janicept

I have a code P0158 (also code P0121) that I am trying to trouble shoot with my husband. I've read the P0158 is an O2 sensor. Does anyone have pictures of where these sensors are so we can look at them? Or any ideas would be appreciated. I've had an engine light on and off since about a year ago. I was driving home from the mountains and stopped at a gas station that probably doesn't sell much premium and though it was just a bad tank of gas. The engine light eventually went off. As time has gone by it's more frequent but still goes off for no apparent reason. We cleaned the air filter and some other things that my husband saw were really dirty when we took that air flow vent thing off.

In the past couple weeks I've had an occasional loss of power. I should also mention it's a 2008 C6 with just over 265K miles on it. Yes 2-6-5K; what can I say I love my car.

smaynor

There are two O2 sensors on each side of the stock exhaust system. The first one is in the exhaust manifold, and the 2nd one is just past the catalytic converter. There are 4 total. I believe P0158 indicates that it's the one at the cats, on the passenger side (Bank 2, Sensor 2)

Does your car have headers? If so, the front sensors have been relocated to underneath the car at the header collector, and the rear ones have more than likely been removed.

With that many miles, it's very possible that one of them has gone bad/burnt/clogged. Easy to replace yourself. Just take the correct size wrench and screw it out, unplug it, plug the new sensor in, and tighten back into the hole.

P0121 is a Throttle Position Sensor. May be an intermittent problem or it may just be bad from so many miles.

Good on you for driving that thing like it's meant to be driven!