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Old 12-30-2011, 01:58 PM   #1
nacho55
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O2 sensor questions keep or remove

I'm in the process of converting my harness and I've been using the information from lt1swap and it's been very helpfull but my harness had a bunch of wires cut that went down to the transmission which is ok because I'm going with a five speed but I think some of the o2 sensors were cut off so I don't have all the plugs, can it be run without them? Also does the temp sensor need to be hooked up as I'm missing that plug too
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Old 12-30-2011, 04:07 PM   #2
BR3W CITY
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Re: O2 sensor questions keep or remove

You need the front 02's, but you can loose the rears and have the CEL turned off in the tune. With no front 02, the computer hunt around trying to maintain a stoich balance, but have no way to know that it does. Run like crap.

I'm not 100% sure on temp sensor, but if you are going to have the ecm control the fans, I imagine you would need it.
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Old 12-30-2011, 05:10 PM   #3
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Re: O2 sensor questions keep or remove

You need the front O2s unless you plan to run a speed density tune which will eliminate all your O2s and you MAF. Talk to your tuner before you think about going this route.

You need the temp sensor, without it your PCM will think it is VERY cold and run very rich.
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Old 12-30-2011, 05:30 PM   #4
nacho55
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Re: O2 sensor questions keep or remove

Ok so I found my temp sensor and have that situated, and other leads to the o2 sensors but like I suspected one side was cut when the person I got the motor from removed it for me, and now with the harness all tore apart I don't know which one goes to which side of the motor, i suspect this will be important fot the pcm, does any one know which pins go to the passenger side, or drivers then I will be able to get them routed properly.
Thanks
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Old 12-30-2011, 09:20 PM   #5
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Re: O2 sensor questions keep or remove

What engine and year are you working on? If you swap O2 banks, it will wreak havoc on your swap! I talked to.a.guy that bought a high dollar harness that the O2s were swapped and it took a long time to figure out why it ran so bad/ rich. The O2s were telling the PCM thatit was lean so it dumped more fuel but the problem is it was using the opposite bank of injectors.
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Old 12-30-2011, 10:19 PM   #6
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Re: O2 sensor questions keep or remove

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Originally Posted by ls1nova71 View Post
What engine and year are you working on? If you swap O2 banks, it will wreak havoc on your swap! I talked to.a.guy that bought a high dollar harness that the O2s were swapped and it took a long time to figure out why it ran so bad/ rich. The O2s were telling the PCM thatit was lean so it dumped more fuel but the problem is it was using the opposite bank of injectors.
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That's what I figured would happen so this is going to be helpful to find out which is which, but the motor is a 2002 5.3l, after looking at lt1swap I have the harness with the flat 4wire o2 sensors, atleast I have one of the plugs, any help would be great
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Old 12-30-2011, 11:06 PM   #7
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Re: O2 sensor questions keep or remove

Not the best source, but they have the wiring diagrams on autozone's site under repair info.
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Old 12-31-2011, 02:16 AM   #8
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Re: O2 sensor questions keep or remove

do you have the sensors yet? if not just get 2 universal sensors and either wire them straight or get the bosch pigtail. I think the universal sensors I used were Bosch 13444
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Old 12-31-2011, 11:57 AM   #9
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Re: O2 sensor questions keep or remove

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Originally Posted by nacho55 View Post
Ok so I found my temp sensor and have that situated, and other leads to the o2 sensors but like I suspected one side was cut when the person I got the motor from removed it for me, and now with the harness all tore apart I don't know which one goes to which side of the motor, i suspect this will be important fot the pcm, does any one know which pins go to the passenger side, or drivers then I will be able to get them routed properly.
Thanks
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Bank 1 sensor 1 low signal blue connector pin #29 tan/white
Bank 1 sensor 1 high signal blue connector pin #69 purple/white

Bank 2 sensor 1 low signal blue connector pin # 26 tan
Bank 2 sensor 1 high signal blue connector pin # 66 purple
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http://ls1tech.com/forums/conversion...71-c-10-a.html
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Old 12-31-2011, 11:58 AM   #10
nacho55
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Re: O2 sensor questions keep or remove

I haven't bought any yet, but those look like a good deal , funny how these little missing parts start adding up
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