Where is the o2 sensors located??

TheForce · 09-15-2011, 05:03 PM

Where is the o2 sensors located on my 2000 Inisght? I cannot seem to find them anywhere. Not even a place where there should be one.

Eli · 09-15-2011, 05:14 PM

They're screwed into the exhaust pipe - one near the engine, one down a little bit further. Pretty much impossible to miss.

All O2 sensors are always in the exhaust tract, that's what they're sensing.

TheForce · 09-15-2011, 05:16 PM

Yup. Just found them.

I was looking under the car for them.

I'm not a car guy.

TheForce · 09-15-2011, 07:24 PM

The post cat sensor is being a bitch. Its frozen on and I'm pretty sure its the one I need to replace.

Eli · 09-15-2011, 07:46 PM

What is your code?

Need more leverage.

Could also try a torch if you have one(heat the exhaust pipe, not the O2 sensor).

TheForce · 09-15-2011, 07:57 PM

P0138. The numbers on the scangauge for lean burn dont move and are stuck on 127. The car still feels like its the EGR valve but I cleaned the plate and tested the valve. When I unplug the EGR valve the bucking goes away. I read somewhere that it could be the sensors causing the bucking if the EGR valve is good and clean. So I'm trying to replace the sensors. From the looks of the old ones they look like they never been replaced and it might be a good idea to replace them anyway.

Leverage did not work.

I don't have a torch but I think I could make something.

I'm giving up tonight and letting it soak with wd-40 and some rust remover stuff. I was wanting to try it out tomorrow but I guess that ain't happening.

Eli · 09-15-2011, 08:03 PM

Errrr

No. Replace the EGR valve. The EGR valve's failure is internal; the carbon track for the potentiometer feedback becomes worn. In my experience, the EGR valve itself rarely becomes clogged with carbon because it's so much closer to the hot exhaust gasses. The reason the EGR plate becomes clogged with sticky, gooey carbon is because it's much cooler than the rest of the engine, causing the exhaust gasses to condense.

Bucking/herky jerky is NOT O2 sensor related.

But yes, P0138 means the secondary O2 sensor(the one farther down) is bad - but that has nothing to do with your bucking symptoms.

You said it yourself, unplugging the EGR valve fixes the problem. That's all the diagnostic you need.

TheForce · 09-15-2011, 08:05 PM

I took apart the EGR valve and the tracks look new and measured OK on the multi meter.

Eli · 09-15-2011, 08:12 PM

Quote:

Originally Posted by TheForce

I took apart the EGR valve and the tracks look new and measured OK on the multi meter.

Replace the damn EGR valve already. :P

If unplugging the EGR valve fixes the bucking, that is all the diagnostic you need, since you said you've already cleaned the plate.

O2 sensors, and especially the secondary sensor, will not cause bucking. Where did you read that? It was wrong.

Eli · 09-15-2011, 08:15 PM

Are you *SURE* that unplugging the EGR valve stops the bucking 100%?

The only thing other than the EGR valve and plate that causes bucking/herky jerky is the fuel injectors.