I need advice. I have a gx 470 2007. Changed out all oxygen sensors but I noticed on one of the circuit box the oxygen sensor connects to was black like it was burnt out. Not the actual sensor I bought but what the end connects to. Is that possible and is it something I can fix on my own. I have 10% mechanic skills. I don’t even know what that wire is called or where it leads too.

 

I should have mentioned that it was on the passenger side upstream. The sensor was close to the right front wheel

 

So the wiring connector was black and burnt? Any chance you could post a pic? What kind of shape was the old O2 sensor and wiring in when you removed it?

 

I knew I should have taken a picture but I didn’t. The old sensor looked fine inside the circuit end. The. Part coming down from the engine looked black inside. I can take a picture and post it. I just need the car to cool down before I can touch anything. The check engine light is still on after driving about 150 miles.

 

That picture will be worth a thousand words at this point. Now, although sometimes it does, it may need to be physically erased, the code/cel that is.

 

After looking at it again, I think that’s the color of the circuit. So what next should I try [img]blob:https://www.clublexus.com/99de1e73-bb92-417e-a4b3-2ae4a1c99264[/img]

 

What codes are you getting????


toyota 4.7L’ are notorious for setting O2 sensor codes with SAIS faults.

Also... if it’s just O2 sensor codes... that doesn’t mean you have bad O2 sensors... it could just be a rich mixture, lean mixture, or catalytic converter problems.
All vehicles, regardless of brand, set O2 sensor codes for rich or lean mixtures.
These can be caused by “false air”, too little air, bad cats, or bad intake air calculations.

Also so low grade fuel can cause O2 sensor codes.


So what codes codes are you setting?