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silly wiring harness/electrical question

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Old Feb 25, 2014 | 08:11 PM
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Default silly wiring harness/electrical question

when i was hooking everything back up in the car the ground wire that comes out by the bank 1 (left side) harness by the O2 broke. i left it for now thinking all of my other grounds are good but now i go to start the car... nothing. can that tiny ground wire be causing my nightmares. i check i have fuel going to the rail but the car acts like it starving for gas cranking and cranking but wont start??? thanks
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Old Feb 25, 2014 | 08:48 PM
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Since the O2 sensor does not have a ground wire (O2 sensor is provided ground via PCM), that ground wire may provide ground to the PCM.
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Old Feb 25, 2014 | 08:51 PM
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yea i know it comes out of the wiring harness right before the o2 but i cant seem to find out what it is or where to track it too. i need to find out what it is and where it runs in the harness. ive cut the loom a good couple feet back and cant find where it started. anyone with ideas?
thanks
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Old Feb 25, 2014 | 08:59 PM
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You referred to it as a "ground" wire. Before it broke, to what did it connect? (on the end that is exposed).

It may be: (a) the wire that supplies power to the fuel injection coils on that bank (switched by the PCM); or (b) the wire that supplies ground to the fuel injection coil circuits.

Last edited by Darkman; Feb 25, 2014 at 09:21 PM.
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Old Feb 25, 2014 | 09:19 PM
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i do know its a ground wire from what it is it has a ring terminal that bolts to the frame rail but the wire it self comes out of the wiring harness a couple inches back from where the bank1 upstream o2 connector sitssilly wiring harness/electrical question-ls1-wiring-harness.jpg

maybe this picture helps i just cant find where the rest of it is
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Old Feb 25, 2014 | 09:29 PM
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If you know that it is a ground wire then all you need to do is ground it to the motor. You don't really need to trace its source.
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Old Feb 25, 2014 | 09:34 PM
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i dont believe its an engine ground. i am in concur with your statement about it being a ground for the coil circuits. it came out of the wiring harness and bolted to the the body the problem is it broke off from the harness. the end is still bolted to the body i need to trace where it broke and put it back together
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Old Feb 25, 2014 | 09:37 PM
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Okay, now I understand.
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Old Feb 25, 2014 | 09:41 PM
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im pretty sure that ground strap goes connected to the block close to the engine mount
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Old Feb 25, 2014 | 09:43 PM
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I can check my car for you tomorrow

Last edited by pimpin78transams; Feb 25, 2014 at 09:53 PM.
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Old Feb 25, 2014 | 09:47 PM
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you guys can see where im confused from the picture it comes out of the wiring harness just a couple inches up from the o2 and me being in a hurry trying to move the wires around i pulled on it and pop that wire comes out of the harness never to be found again and what do you know about that time my car cranks but stops starting. crazy thing is i cut the harness open about a foot up and no trace of where it came from
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Old Feb 26, 2014 | 03:12 PM
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Check the ground splice in the harness. You will see where all the grounds come together and come out as one wire.

http://lt1swap.com/removing_ground_from_splice.jpg

Last edited by lsxRanger94; Feb 26, 2014 at 03:23 PM.
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