How many O2 sensors?

[movin2stereo]

I have a 98 ZR2 with the 4.3.The 8th digit of the VIN is a W.I'm looking for O2 sensors online.Online tells me that I will need 4(2 front & 2 back).I crawled under the truck and I see the 2 up front,but only 1 after the cat.So how many are there,3 or 4?

[dmbrisket 51]

3 for all i know, one post cat, and i beleve bank one and two

[jchupella]

you have four dude, 3 on your y pipe, and the one right after the cat. you have one on each side of the y-pipe coming off the manifold, one about 1 foot before the cat, and the one right after the cat

[dmbrisket 51]

Originally Posted by jchupella

you have four dude, 3 on your y pipe, and the one right after the cat. you have one on each side of the y-pipe coming off the manifold, one about 1 foot before the cat, and the one right after the cat

why the hell did they put so many of them on there??? its waistful and more of a pain in our asses isnt it??

[rlith]

Originally Posted by dmbrisket 51

why the hell did they put so many of them on there??? its waistful and more of a pain in our asses isnt it??

ODBII compliancy requires 3-4 02 sensors.

[movin2stereo]

Originally Posted by jchupella

you have four dude, 3 on your y pipe, and the one right after the cat. you have one on each side of the y-pipe coming off the manifold, one about 1 foot before the cat, and the one right after the cat

I have seen the 2 after the exhaust manifolds and the one after the cat.I'm going to crawl under it again and look for this one before the cat.

[movin2stereo]

Confirmed,I only have 3.

[BlazerLT]

The one after the cat doesn't need to be replaced, it just monitors cat efficiency.

[dmbrisket 51]

Originally Posted by movin2stereo

Confirmed,I only have 3.

thats all i have ever found

[movin2stereo]

Which one is referred to as bank one,that's the one tripping the code.

[dmbrisket 51]

Originally Posted by BlazerLT

The one after the cat doesn't need to be replaced, it just monitors cat efficiency.

so your saying i can cut the cat off with no problems?

[movin2stereo]

Originally Posted by dmbrisket 51

so your saying i can cut the cat off with no problems?

I would like to know the answer to that question.I've done that in the past to other cars I've had.

[BlazerLT]

No, don't cut out the cat.

Does nothing for performance.

What I meant was that you don't need to replace the replace the post cat O2 sensor. You still leave it in there though.

Bank 1 is driver's side.

[movin2stereo]

Originally Posted by BlazerLT

No, don't cut out the cat.

Does nothing for performance.

What I meant was that you don't need to replace the replace the post cat O2 sensor. You still leave it in there though.

Bank 1 is driver's side.

Thanks.

[dmbrisket 51]

well yes i will get preformence out of it, mine was soooo plugged up b4 i switched to a high flow it was robbing me of all my power and gas mileage, i was just woundern if i would of cut it out, would it have been ok, instead of putting 180 into a highflow cat