BobMax

Bank 1 Oxy sensor questions:

What tool do you guys use to remove this? I have an Oxy sensor socket but there's no way I can fix it on top of that sensor... and there's no way I would be able to get a ratchet or extension on it if I did. I hate to use an open end... seems like a good way to round it off an turn it into a bad day.

Is a 3 wire replacement OK? I ordered a replacement and it came in as a 3 wire. Do the cross two of them internally somewhere, or do I need a different sensor?

Thanks,

sanford7575

Never heard of a 3 wire O2 sensor.
I have an O2 sensor wrench, but usually just use an open end wrench with plenty of pb blaster.

asand1

iTrader: (1)

You have the wrong sensor. After you do get the right one, you can cut the wires off the old one and use a box end wrench. Also you can probably rent an O2 socket for $50.00 deposit.

Do you have cali or fed emissions?

asand1

iTrader: (1)

Looking at Rockauto, all the upstream sensors are 3 wire, with the after-cat sensor being 4 wire. Which sensor are you looking at?

The connector should be in this area.

BobMax

Fed emissions. I'm trying to replace bank 1 (underneath, on the curve before you get to the sensor on the car)

The connectors are all in front of the engine, just behind the top of the radiator, in front of the cyl bank. Can't take a picture now as it's dark out.

I'm pretty sure I followed the correct wires and pulled the correct connector, but all those rock auto parts are definitely 3 wire connectors. Maybe I didn't follow the wires correctly. Sure thought I did. Just to verify:

- the upstream front/bank2 is the one that you can see and access from above
- the upstream rear/bank1 is the one that's on the inside curve of the header as it bends 90 degrees to get to the cat
- the downstream is the one that's in the front of the cat

Is that correct?

BobMax

FYI - I have an O2 socket, but it's too tall to fit in there. Looks like the cut and box end is the only choice. Not sure I can find a 6 point box though... maybe cut and try to use a conventional deep socket.

2brosgixxer

Put some vise grips on that bish along with some pb blast if they will fit. Clamp them tightly so you don't round the sensor. Hit it with a hammer if you can get to it or a pipe as an extension for leverage.

BobMax

Following up here in case anyone else runs into this...

Turns out that the car is CA emissions spec (ran another thread to figure out that most 99's are, and it says so on the label under the hood) even though it was sold on the East Coast.

That meant I had FOUR O2 sensors, and the one I was looking at was considered a downstream sensor (still looks ahead of the cat to me, but who am I to question it ;-)

I went hunting again and found the bank1 upstream sensor, connector located where asand1 indicated. The other three are in that front array, the bank 1 upstream is elsewhere.

You can actually fit an o2 socket on this one using a 12" extension that comes out by the strut/axle. That made removal a snap.

Amerikaner83

iTrader: (17)

on the Cali specs, there are two "downstream" O2 sensors...behind the PRE-CATS...not the main one. the upstream ones are before the pre-cats, the downstream ones are after.

Fed spec has one O2 in front of each precat, and one after the main cat.