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Old 02-26-2007, 08:55 PM   #1
bbchevy
87 Wanna Be K30
 
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O2 sensor???maybe?possibly???

I put full length headers on my 87 and now it has no power. The truck barely moves when its cold and when its warmed up it bogs out really bad. I cant really drive like this. My 0-60 time is about 10 minutes. is it possible that i put the o2 sensor too far away when i welded the new fitting in? its on the exhaust, about 6in before the collector. i heard it needs to be with in a foot of the head. should i move it to a header tube?

thanks guys

-Scott
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Was: 1987 V10 Silverado
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Is: A wanna be K30
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Last edited by bbchevy; 02-26-2007 at 08:58 PM.
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Old 02-26-2007, 11:28 PM   #2
HuggerCST
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Re: O2 sensor???maybe?possibly???

Quote:
Originally Posted by bbchevy View Post
I put full length headers on my 87 and now it has no power. The truck barely moves when its cold and when its warmed up it bogs out really bad. I cant really drive like this. My 0-60 time is about 10 minutes. is it possible that i put the o2 sensor too far away when i welded the new fitting in? its on the exhaust, about 6in before the collector. i heard it needs to be with in a foot of the head. should i move it to a header tube?

thanks guys

-Scott
Good question. I wouldn't think that the location would affect it that much, but I guess it's possible. I just finished welding mine into the same place, but haven't finished installing the harness yet, so I haven't started it. I'm putting a 87 TBI & harness into my 85. I'll let you know how mine runs.
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Old 02-27-2007, 12:56 AM   #3
bbchevy
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Re: O2 sensor???maybe?possibly???

Yea i heard the o2 has to be a certain temp to function properly. and making it that far away messes with it. that and the fact that it 30 degrees here so the exhaust doesnt get that warm in the first place, right now. i think im going to move it to a header tube.... but i really dont wanna move it
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Was: 1987 V10 Silverado
TBI 350/700R4/208 with 3.42 gears

Is: A wanna be K30
330hp 350/465/205/D60/14FF with 3.73
hydroboost, 4 Core radiator, electric fans, Centerforce Duel Friction, Locker, 6inch Soft ride lift, etc....
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Old 02-27-2007, 04:16 AM   #4
84slopwaggin
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Re: O2 sensor???maybe?possibly???

I just installed headers on my 85. When I went to purchase reducers at the local speed shop some that they had in stock had the bung for the O2 sensor. I take it thats where it needs to go is in the reducer or maybe the collector itself. What type of headers did you install?
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Old 02-27-2007, 05:38 AM   #5
MylilBowTie
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Re: O2 sensor???maybe?possibly???

If it is a heat issue I would get a heated O2 sensor (three wire).
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Old 02-27-2007, 10:44 AM   #6
ChevyTech
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Re: O2 sensor???maybe?possibly???

Quote:
Originally Posted by bbchevy
The truck barely moves when its cold and when its warmed up it bogs out really bad.
The O2 voltage reading is not used to determine the fuel mixture during “Open loop” (cold) operation.
Anything else you can think of that you changed at the same time you put the headers on?
How stock is everything else?

Quote:
Originally Posted by bbchevy
Yea i heard the o2 has to be a certain temp to function properly. and making it that far away messes with it.
True

Quote:
Originally Posted by MylilBowTie
If it is a heat issue I would get a heated O2 sensor (three wire).
With headers, I would only use a heated O2 sensor.
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Old 02-27-2007, 10:48 AM   #7
HuggerCST
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Re: O2 sensor???maybe?possibly???

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Originally Posted by ChevyTech View Post

With headers, I would only use a heated O2 sensor.
How should it be wired?
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Old 02-27-2007, 12:13 PM   #8
ChevyTech
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Re: O2 sensor???maybe?possibly???

Quote:
Originally Posted by HuggerCST View Post
How should it be wired?
Kits for retrofitting should come with instructions.

For the Three wire sensors:
One wire will connect to the same wire as the Old O2 sensor did.
Another will connect to power when the truck is running.
The remaining wire connects to ground.

Make sure you connect the correct wires to the correct places.

I would think there are other board members that have good information on this. Maybe even instructions, which came with theirs, they can post.


These sites show how 4 wire O2 sensors are wired on newer vehicles from the factory.
http://shbox.com/1/HO2S_connector.jpg

http://autorepair.about.com/library/...bl786a-lib.htm
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Old 02-27-2007, 12:16 PM   #9
HuggerCST
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Re: O2 sensor???maybe?possibly???

Quote:
Originally Posted by ChevyTech View Post
Kits for retrofitting should come with instructions.

For the Three wire sensors:
One wire will connect to the same wire as the Old O2 sensor did.
Another will connect to power when the truck is running.
The remaining wire connects to ground.

Make sure you connect the correct wires to the correct places.

I would think there are other board members that have good information on this. Maybe even instructions, which came with theirs, they can post.


These sites show how 4 wire O2 sensors are wired on newer vehicles from the factory.
http://shbox.com/1/HO2S_connector.jpg

http://autorepair.about.com/library/...bl786a-lib.htm
Thanks!
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Wynne
70 CST short fleet Hugger orange & white, 350/350, ps, pb, air, tilt, tach/vac/speedwarning, original buckets, AM/FM, oak bed floor, shoulder belts, 3.5"/5.5" drop, 20" American Racing VN425s.
Build thread
53 Chevy shortbed
69 Camaro

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