Adding an o2 Sensor

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atvjoey

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Hello all,

I have a TBI truck that has been absolutely cannibalized by somebody and one of the things I've realized is that it does not have an 02 sensor since someone put on shorty hooker headers on it. I have not found any wiring for it or any other o2 sensor related hardware so does anybody have any information and/or pictures of what I should be looking for? Does it plug into the ecm and all I need to do is buy one? Where does/should the wire come from? Also since I can't weld has anybody used the clamp-on o2 bungs with success or is it worth it to pay someone to weld it. Thanks guys!
 

AuroraGirl

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Hello all,

I have a TBI truck that has been absolutely cannibalized by somebody and one of the things I've realized is that it does not have an 02 sensor since someone put on shorty hooker headers on it. I have not found any wiring for it or any other o2 sensor related hardware so does anybody have any information and/or pictures of what I should be looking for? Does it plug into the ecm and all I need to do is buy one? Where does/should the wire come from? Also since I can't weld has anybody used the clamp-on o2 bungs with success or is it worth it to pay someone to weld it. Thanks guys!
O2 sensor needs to be a specific distance after usually the collection of the exhaust, typically, and the location can be varied if you have a heated sensor retrofited inplace of the original not heated sensor. the wiring im not sure where it originates but they probably tucked the connector away or just hacked it off. But I recommend going for a set of OE manifolds with the proper fitting if you arent pushing for horse power but if you want to keep your headers then there is some fab work needed.
 

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The ones I seen have the sensor on the collector right after the four tubes enter it. But your system may call for the sensor to be up near the engine. In that case one header tube will be okay but where is the question. If you can make out what kind of headers you have, you can call the company and ask them, they will know what kind and where it goes.
And for wiring, is all of it gone out of the truck, or just the oxygen sensor wire? You need to head for the junk yard for what you need. I hope you don't need the whole thing because that's going to be expensive and/or will take you a while to put in, or both. Maybe you can find someone who has taken theirs out, or stripped a truck and has it in good shape enough that you can use it. Maybe they will sell it to you for a small amount.
 

75gmck25

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I think the stock setup is an unheated 2 wire sensor, so it should be in the header pipe up close to the exhaust manifold. If it’s too far away from the engine it will not heat up and work properly.

Some aftermarket setups use 4 or 5 wire heated sensors, but I don’t know if they can be retrofitted.
 

RoryH19

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Let's not overthink the tbi system of these trucks. They are primitive compared to new cars with pre and post cat multi-wire o2s. It's just one o2 on the left side just above the y-pipe.
 

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atvjoey

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So I found the wire with the connector tucked away behind the engine in between the firewall. Now I just have to figure out where to add it and how. I can't weld so I found a clamp on o2 **** that you just need to drill a hole in the exhaust to install. Where would you guys recommend putting it if the truck has shorty headers and no cats? I'm trying to make it functional for as cheap as possible to get this truck running right.
 

akchevrolet

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Do you have a picture. you can also buy collectors that have the o2 **** prewelded on them then all you have to do is change collectors and put the o2 sensor in. if its far enough away a 3 wire heated one is said to be best since the exhaust isnt heating the 1 wire sensor anymore, if its close enough to the heads then i think the one wire sensor should work. and its on the drivers side.
 

75gmck25

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I used one of the clamp on O2 fittings from Summit and it works fine. Just make sure you figure out the angles and allow space for the entire clamp.

The sensor has to be oriented at an angle where moisture does not collect, so the wiring will be pointed up and you need clearance above. The two band clamps for the b u n g also need some clearance so that you can tighten them down. They stick out more than I expected.
 

75gmck25

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Just try searching with Google for an O2 sensor hole instead of a sensor b u n g. As they always say - words matter.:)
 

akchevrolet

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google works using b u n g. you dont get r a c y **** stuff hahaha.
 

akchevrolet

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dumb that r a c y is edited
 

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@atvjoey,

And back to what I suggested is, you contact the header mfg. and ask them where their other headers similar to yours would the o2 sensor be placed. Like @75gmck25 said probaly up near the exhaust manifold or down on the collector. He's right about allowing space around these things because you also have to allow the space for the **** as well. If you can't find the collector with the **** already welded on, and that is if you can change out YOUR collector, really try and find someone who knows how to weld and let them weld the ****. Even though the clamp on's work you need to allow space for the clamp to! I understand that you may not like this idea, but you may need to look for a set of headers with the **** already on them.
 

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