Camden

Hello,

I'm in the process of replacing my precat and postcat o2 sensors. I am wondering if there are any other sensors (that may help increase performance) that I can/should replace. My car has 125,000 kms on it. It is a 2004 Honda Civic SI (CDN). It most likely still has all the orginal sensors in it.

Muirsy

nope no other o2 sensors

where in canada are u located?

Camden

I'm located in Vancouver B.C.

Now I opened my hood, I was looking down at the exhaust. About 1 foot down from the top of the engine block I located a sensor. Is that my precat or postcat sensor? Where is my cat located?

xRiCeBoYx

iTrader: (22)

If you jack your car up and get under it, you'll see the both of them. The one at about the 90º bend of the downpipe is your pre-cat. Right before the flange to the mid-pipe is your post-cat

Camden

Riceboy, could I convince you to take a picture of each for me please? I'm going to replace them both and I don't want to put the wrong one back in lol....

So your saying the precat is closer to the engine (follow the exhaust system) and the postcat is further away from the engine if your following the exhaust system?

So under the vehicle, looking up towards the sky, just below the exhaust manifold, thats my precat?

xRiCeBoYx

iTrader: (22)

Yea. If you jack up your car, it's kinda easy to find the cat. Just look for 02 sensors before and after it..

I'll see if I can get under my car.. Lol

xRiCeBoYx

iTrader: (22)

Yea dude.. I tried, but it's not happening right now. When you buy them, assuming you buy Honda OEM, they're marked with their own part numbers.. Just make sure that when you get them, make sure that you mark which part number is the pre- and post-cat sensors.

sdaidoji

iTrader: (1)

Look here for some helping readings...
https://www.civicforums.com/forums/1...s-manuals.html
And no, they will not help increase performance, they will help you recover what you lost.
Anyway, don't think the O2 sensors will last that long. They "likely" have been replaced before, but not sure, only the PO will know.

Mad Dog Tannen

You have 16 02 sensors. One in each valve...lolololol

Get a 02 sensor socket if you don't already have one cause they are awesome!