Or do you have to be under the car?

 

Yes.

On my 86 Z28 its on the Drivers side exhaust manifold. Sort of a white cylinder type object with a silver heat shield on it and a wire coming off it.

Definatly can get it from the engine bay.

 

Beautifical. I wanted to make sure. I thought that was it, but the photo in the haynes manual sucked.

 

Well, this photo may not be any clearer, but I'll give it a shot:



You should be able to reach it from the top with a 13/16" or 7/8" box wrench or deep socket. Unplug the connector and slide the wrench over the sensor wire onto the hex. If you have a very deep socket, you can carefully fold the wire and connector into the socket and slide it onto the hex.

When you pick up a new sensor, also get a small container of anti-seize compound. The sensor comes with a little already on its threads, but it is rarely enough. Apply the compound to the OLD sensor, then thread it into the hole by hand, working the compound into the threads of the exhaust tube. Work it back and forth a few times to evenly distribute the compound, then remove the old sensor and install the new one. If there is only a little compound on the new sensor, carefully apply a bit more, avoiding the sensor tip. Connect the electrical connector (you can apply a bit of dielectric silcone grease to the sealing boots if you like) and you're done.

If you have some difficulty in getting the old sensor to break loose, you'll understand the desire for a little extra anti-seize compound (for the next time you change the sensor - about 30,000 miles away).

 

I have a feeling my breaker bar might come in handy. Where do I get anti-sieze compound?

 

Oh, they'll have antisieze at any local parts place for the most part. Loctite makes a good product.

 

i'd just recommend getting the $9 deep socket with the missing side to let the wire out ( O2/oil press sender tool, unfortunately wont fit the oil pres sensor on these cars...)

it's much easier to get at from below. no matter what i did to mine it wouldn't come off, so i just had a shop put a torch on it and it came off in a couple minutes. (to get it to the temp they did, i couldn't have really worked under the car very easily)

but it's definitely one of the most under-appreciated parts, both for driveability and emissions. when i did it on the car i had just bought, gas mileage jumped from 12ish to 17ish.

 

It's looking like I'm going to need a MotorVac trip anyway, so I might just get them to do it while its up. From my understanding, you need new plugs when you do that, so it'll all be good (I've got new plugs, 3k miles on em... )

 

new plugs with motorvac? what's that?

In doing my O2 I just used the O2 socket and 2ft of extensions on my ratchet. Done from the top. Run the engine for a minute and that'll heat it up nicely. No breaker bar needed when I did it.
I put it back on with the extensions and ratchet as well. No problems.

 

i just found out my sensor is bad as well but for me b/c of the headers i have to go at it from below

 

If you're putting a new sensor in, just cut the wire off and slide a deep socket over it. That's the most reliable way to get it out (o2 sockets can flex), and then use a wrench to install the new one.

 

I just replaced mine with the knock sensor this weekend. it helps if you have small hands but once you wedge in there it doesnt really take a lot of effort to loosen it and it was a little easier getting the new back in (once your hands are already sliced and bleeding you just dont care anymore.) get the o2 socket from auto zone. 15 returnable deposit. took me 5 min to do.

 

ok stupid question do we 3.1l 's have 1 or 2 sensors????

i'm under the impression that i have one
currently sticking out of the bottom of my headers


the reason i'm asking is i just tried to pick up the bosch #12014 oxy sensor tomp mentioned in a different post to me for around $26

but this cat in auto zone (i just left there not 15min ago)
is trying to sell me two one for in front of the cat and one for behind and both were over 60 bucks



(but then what else is new)

 

****. My problems exploded...


https://www.thirdgen.org/techbb2/sho...hreadid=154895

 

MotorVac: They hook a machine up to the fuel lines, runs the car on gas and a special chem. for 45 min, and then take it out at WOT for 5 min. All sorts of black stuff flies out your rear, instead of sitting on your valves

 

Cool. That stuff doesn't clog up the cat(s)?

 

Doesn't apear so...