Just requesting some help... I'm around 95% sure my O2 sensor is bad. I've spent the last two days trying to get to the thing to check it but haven't been able to.

So... Is there a way to check the O2 sensor's operation without a scan tool? (There are no codes so it does react, but very slowly I think.)

Is there a way to physically check the sensor?

And most importantly because like I said I really think it's bad, how do I get to the thing? '91 Z28 LB9, the sensor is on the exhaust manifold, blocked from every angle I can think of. So is there an easy way to get to this? If major parts have to be removed then what's the easiest way? Thanks in advance for your help.

 

To answer your first question, you can bench test the o2 sensor. Take it out and put it in a vice grip. Now take a torch and heat up the tip. You are now depriving the o2 sensor of oxygen. Take your volt meter and measure the voltage coming out of the 1 wire while grounding to the threads of the sensor. The voltage should go up past 800mv or .8v. If it doesn't, bad sensor.

For question number 2, they sell o2 sockets at almost any auto parts store.

 

Thanks alot this is my first car, I never knew there was such a thing as an o2 socket. Trying to get that thing out with a wrench was impossible.

 

Wrench; impossible. O2 sensor socket; doable but still a PITA!

 

Wrench - two days with no progress on the old sensor. With a new non frozen sensor i could probably get it in about an hour, by disconnecting and sliding a 12 point box end up the wire from underneath you can reach it an turn it a few degrees. That's what i tried at first but it's a huge PITA.

With the socket, two extenders, and a piece of pipe it was easy. Took 10-15 min.

 

What about the swivel joint? I broke the one from tiawan, Japan, and the lifetime garanteed Napa before I had any sucess!