O2 sensors

[My_Teal_V6]

Did a search for O2 sensors and found some good info. Just want to clearify, the 3.4 has 3 sensors? 1 on each manifold and one after the cat correct?
Like I had posted before my car seems to be losing power, and since I have no clue what the previous owner did I'm changing the plugs, wires, as well O2 sensors.
On Monday I will be getting my new exhaust on. A Magnaflow cat. 2.5" cat back to a Flowmaster 80 series with 3" duel tips. Hopefully all this will help. Now, will the Magnaflow cat have a place for the sensor, or is this one not really needed?
Also this week I'm replacing the WP and putting in a 180* thermostat.
Sorry for all the questions, but this is my first big tune up to the car in 10k miles. It has 74K on it now.
Thank you in advance....

[My_Teal_V6]

okay...moderators, you can remove this post. The other post about the sensors answered my questions.

[98Camaro3.8]

You can delete the post yourself. Click edit and chose the box to delete the post. ;)

[BobbyZ72]

Since yall dont want this post im going to take it over and clam it [img]graemlins/naughty.gif[/img] My 1997 camaro with about 105k on it has started getting bad gas milage, its at about 23 mpg hwy, i used to get 27, i have changed nonthing. I have been told i may want to change my o2 sensors. I went to the auto parts they told me i need 2. one goes in front of the cat and one right behind it. I buy both, but each is slightly diffrent in size and plug type. I jack up my car and change one, and move to the next one, but the one infront of the cat is the exact same as the one in rear of the cat. So the second o2 senser i pick up has the wrong plug on the end, its a long skinny one and i need the square male plug. So i say no prob ill just go back and get another one. I get it and install it, then i notice another o2 senser right next to my engine, and then another on the other manifold. [img]graemlins/rant.gif[/img] So this time i go back and tell the guy i need the 2 o2 sensers that go on the manifold, he hands me 2, but these 2 are the same 2 that i just installed with the square male plug. The 2 that i need both have square female plugs on them. My queston is,,is an o2 senser an o2 senser?? and has my car been messed with in the past before i owned it? In what order do the o2 sensers go? And why on earth do i need 4, shouldnt 1 do? I know you have heard me say it before, here it is again...Chevrolet mechanical engineers, id fire them all. [img]graemlins/rant.gif[/img] [img]graemlins/twak.gif[/img]

[BobbyZ72]

And at 80 bucks a pop...they aint cheap.

[BobbyZ72]

Originally posted by 98Camaro3.8:
Manifold sensors:

97+ are the same. Delco AFS109
95-96 are different (think the connector changed here). Delco AFS75.


Other sensors (1 or 2 depending on year):

95 has a different connector. Delco AFS90.
96-97 are a Delco AFS97.
98+ is a Delco AFS116.

O2 sim for 98+ will fit 96-97 post cat connector, but not 95.

Never mind, found this in the search, anwsers most of my queston, my car is correct.

[phil97.3.8]

why delete this now? , it may help somebody else!

[Flowbee V6]

Originally posted by phil97.3.8:
why delete this now? , it may help somebody else!

Yea, I'm learning a lot from this thread. Im in the same situation as Bobby, and this might save me some time

[My_Teal_V6]

I replaced both the manifold O2 sensors and the car acts like it's new. I agree with firing the GM engineers, I replaced the plugs and wires, man what a PITA...
But she runs 100% better now.

PS: I bought Bosch O2 sensors for $21.00 a piece plus got a $10.00 gas card from Bosch for the purchase.

[BobbyZ72]

ok...YOU HAVE TO TELL ME WHERE YOU FOUND THEM FOR THAT PRICE!!! [img]graemlins/banana.gif[/img] lol. My car runs good, im thinking it can do better then 23 mpg...i know it can.

[viper98885]

That's the price for the single-wire sensor used in the 3.4L V6s

[BobbyZ72]

OH, i was like, man i got ripped off. I was going to buy the ones for $21 put them in the boxes of the ones i bought and take them back..lol..not really, but i was thinking about it.

[My_Teal_V6]

Sorry, my mistake. didnt read all the post. Yes they are for the 3.4L

[BobbyZ72]

its cool