Thread: Oxygen sensor fitment issues with headers

Don't you know I don't read anywhere and don't even think about the upstream sensor as I'm buying and installing my headers. Finally remember I need an o2 on my sd headers, rear one deleted, and the thing won't fit due to my firewall. Has anyone tried a c5 o2 sensor or hammering the firewall with the headers still installed? Installation was really something and I'm not trying to go ahead and disassemble and do it all over again. You speed daddy guys have to know an answer to this one

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Yup. I guess this is one of those "unspoken" things in the gp community as I had to figure this out myself.

You have to pound out the fire wall. I did it with headers still installed. Took a socket extension and hammered the crud out of it. Good luck!

Originally Posted by Fivefingerdeathpunch

I wouldn't say unspoken, it's been well known since like 2011-2012 when they became popular headers.

Beat the fire wall or install the o2 sensor in the cross over pipe, many do this as well.

So neither of you guys heard of using a c5 sensor?

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I haven't heard of a c5 sensor although I ran into the same problem you did. The best option I found was to plug the o2 bung the headers came with and weld in a new bung a little further down. If you don't know how to weld most exaust shops will weld in a bung for about 40$ which is probably cheaper then the sensor your talking about. Idk how big the c5 sensors are but, even if they were an inch shorter id still be nervous about what happens when the motor is jerking around during hard shifts and going WOT that it still might hit the firewall.

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Not only did I document it ... I posted tons of pics too. Should have been easy enough to find. I liked to use an air hammer .. takes some finesse, but it's doable and works best for massaging the firewall.

Interesting. I've been through literally all the how-to posts and never saw it! Must have looked right past it. Sorry Bill! And no, I hadn't heard of using the c5 sensor, but I had an extra bosch o2 sensor lying around which is why I used it. Lol

Having another bung welded is a good idea, however keep in mind you can't angle too far down because of condensation. A buddy of mine did this and went through three o2 sensors before he realized his mistake!

Originally Posted by wstefan20

Interesting. I've been through literally all the how-to posts and never saw it! Must have looked right past it. Sorry Bill! And no, I hadn't heard of using the c5 sensor, but I had an extra bosch o2 sensor lying around which is why I used it. Lol

Having another bung welded is a good idea, however keep in mind you can't angle too far down because of condensation. A buddy of mine did this and went through three o2 sensors before he realized his mistake!

So where should I have it welded?

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Originally Posted by wstefan20

Yup. I guess this is one of those "unspoken" things in the gp community as I had to figure this out myself.

You have to pound out the fire wall. I did it with headers still installed. Took a socket extension and hammered the crud out of it. Good luck!

You were able to hammer the firewall with the downpipe still in the "tunnel"?

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Originally Posted by wstefan20

Interesting. I've been through literally all the how-to posts and never saw it! Must have looked right past it. Sorry Bill! And no, I hadn't heard of using the c5 sensor, but I had an extra bosch o2 sensor lying around which is why I used it. Lol

Having another bung welded is a good idea, however keep in mind you can't angle too far down because of condensation. A buddy of mine did this and went through three o2 sensors before he realized his mistake!

FWIW if you are looking for anything I posted in How to, just search on easy and billboost37.
http://www.grandprixforums.net/threa...ht=easy+header

Any muffler shop will weld for cheap. Any place before the catalytic converter will work really. I'd probably do one right before and angled down from the horizontal 30 degrees or so.

Yeah. I just took the o2 sensor out, grabbed a hammer and some punches I padded with cloth etc. and pounded away! Lol

Somewhere there are tons of pics. Not in that thread though.

Originally Posted by blueanchorgtp

So where should I have it welded?

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Anywhere as long as its before the cat. I had it welded into the little u bend although that was a bad idea because I'm lowered and have bottomd it out multiple times to the point where I'm going to have to have that section replaced since its so smashed in.

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Originally Posted by blueanchorgtp

So where should I have it welded?

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This question was answered before you even asked it...look five posts above your post and find FFDP's post.