ok wire by wire hacked wiring harness for ls1

[chevybuilder18]

ok so when i got my LS1 5.3 liter engine i did get the whole wiring engine management for the engine, just the junk yard hacked it. painless wiring has a kit for it for 800 bucks but i can easily save that by doing it myself. one wire at a time. i think it would be something to experience and something i can proudly say i know how to do with an EFI system, so it doesnt look so intimadating to me or others. If any one can tell me if i have the right computer management box for this, let me know. its a newer style 01 for a 350 vortec chevy(first gen) it says green black red and white on it and has a four plug ins, but i was told it wouldnt work and id need this hot looking aluminum computer, and the person who told me it might not work for my deal since mines coil to plug, and i have 8 coils instead of a distributor but that doesnt rule anything out with computers does it?

[mooseknuckles]

you should have a pcm that looks somethin like this....

[mrhino]

the one you are describing aint gonna work. I redid a stock harness on my 71 "silver dollar" It wasnt that bad, but if your gonna start with a harness that has been completely cut. And your starting from scratch. I wouldn't do it. Do yourself a favor & buy a harness that is already to go. Plug n Play or find a stock harness and remove the wires you dont need.

[chevybuilder18]

ok i really want to do this by myself. Ik it looks frustrating and all but if a 70 year old can put one in his elcamino and do his one wire at a time ik its looking time consuming but its like fishing.
This thread is to demote intimadation against wiring it. It actually aint that bad were they spliced it. Its actully got one huge loom and the smaller idk at the moment looking at it but its all there. I could also make a diagram, maybe show others how to DIY.
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[mooseknuckles]

good luck!....lol.

[rfmaster]

IMHO age has nothing to do with it. Just get yourself a comfortable, warm, well lit workplace and go for. Kitchen is a good spot, but the old lady of the house may have something to say about dragging harness in. The key is to keep good notes, label all connectors and just take the time. Walking away, after getting tired, is perfectly acceptable, but keep on working it until it is done.
I am not a motivational speaker, but I have done harness with hundreds of circuits and that's what it takes.


//RF

[chevybuilder18]

here is a better photo. This is actually the picture i wanted to show the first time, but you can see the first one is sensors and such
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[fastlane]

Chevybuilder18's got the right idea. wiring is QUITE intimidating. I got a box of wires with my truck, no idea where they go, no labels, no nuthin. I can't help you, but good luck anyhow.

[mooseknuckles]

my harness looked the same as that!....only shorter..lol....after researching a little, I found it would be easier to spend $500 and buy a stand alone harness which I knew was going to work when I turned the key...plus I had never done one before....

[chevybuilder18]

Originally Posted by mooseknuckles

good luck!....lol.

thank you! Lol. That computer you showed looks like what i need. Ill keep and eye out looking for one, there not to expensive, but these wiring deals are.

Originally Posted by rfmaster

IMHO age has nothing to do with it. Just get yourself a comfortable, warm, well lit workplace and go for. Kitchen is a good spot, but the old lady of the house may have something to say about dragging harness in. The key is to keep good notes, label all connectors and just take the time. Walking away, after getting tired, is perfectly acceptable, but keep on working it until it is done.
I am not a motivational speaker, but I have done harness with hundreds of circuits and that's what it takes.


//RF

walking away from it and taking breaks, lol thats the only time its getting walked away from. Im hoping alot of people dont shun me for it. Im dertimined. Need a wiring diagram but there is no books so im left with retracing em all the way back from the engine to the computer box.. Color coded isnt an option
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[chevybuilder18]

Originally Posted by mooseknuckles

my harness looked the same as that!....only shorter..lol....after researching a little, I found it would be easier to spend $500 and buy a stand alone harness which I knew was going to work when I turned the key...plus I had never done one before....

i have never done one either. Lol but after seeing what i saw i never seen such things to be honest. This guy had it done.
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[Firebirdjones]

They are color coded and pinned, if you have the GM wire diagrams you can trace everything. Most of that stuff is all over the internet and would be easier to search than myself trying to explain it.

You will need a different computer (gen 1 vortec stuff is COMPLETELY different).

I've done a few retro swaps for myself and others, and in the end (especially if doing it for a living) the splice and trace method on a factory harness is very time consuming (and not cost effective for myself).

Since you are starting with a harness that's been hacked already (thanks to the junkyard, very typical) you would be better off in my opinion to either grab another complete harness from the junk yard and pull it yourself,,,,or get a ready made plug and play harness and eliminate all the hassle.

Since you don't have a computer, and your harness is hacked, Frankly I'd go the custom premade harness route because most places will also supply the computer already custom tuned that eliminates all the stuff you don't need.

I've been using Howell for years without a complaint, but there are many others if you want to shop around. I find Howell competetive on prices, and their tech support is excellent. A computer and harness ready to go, along with new 02's, new MAF, only sets me back $800,,,,and these are sensors you should be replacing anyway while doing the swap if you want a solid trouble free rig ready to go thousands of miles.

Personally since your harness is hacked up, and if you are determined to go through with it rather than start with a better harness, I wouldn't recommend splicing into that and trying to extend the wires unless you are extremely competent in your soldering skills. It's a recipe for troubles later down the road, and can cause higher than normal resistance. Your best bet is to remove those cut wires completely from beginning to end and start fresh with proper color coded/gauge wires to eliminate any possible trouble years down the road.
It's going to require specific wire connectors and weather packs, and gets really involved (some of them have to be sourced and are not available local), and will nickle and dime you to death if you do this properly.

Plenty of hack jobs out there though where people try to do this as cheap as possible. I've seen some stuff that is down right scary I wouldn't even touch.

Goodluck with it, it's definately an experience you'll remember

[comegetsome2003]

I got a harness about 2 years ago from Current Performance. I paid around 650 for it. When i put a LS motor in my first square dually it took me longer to decide where to mount the computer than it did to wire the motor and trans.....everything was labeled great and it was all direct plug in....i wired the whole motor and trans in about an hour....i had to pick up a PCM from junkyard it was 35 bucks and pay a guy to tune it and turn the VATS off that was 200 bucks and i was ready to ride....and aftermarket harness is def worth the money in my book
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[rfmaster]

Originally Posted by chevybuilder18

thank you! Lol. That computer you showed looks like what i need. Ill keep and eye out looking for one, there not to expensive, but these wiring deals are.


walking away from it and taking breaks, lol thats the only time its getting walked away from. Im hoping alot of people dont shun me for it. Im dertimined. Need a wiring diagram but there is no books so im left with retracing em all the way back from the engine to the computer box.. Color coded isnt an option
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You can find wiring diagram at LS1tech.com (you'll have to sign-up for user id) - it is do able despite naysayers.

http://ls1tech.com/forums/conversion...schematic.html

/?RF

[mrhino]

It sounds like you are determined to do this, I admire you for that. However when you have several people who have done this swap telling you you should look for another harness either stock or aftermarket. you should listen. I dont think anyone on here is trying to talk you out of taking this on. Its just You asked the question and wanted real feedback from people who have done it. And that's what your getting. I agree with firebirdjones and others. It will be very difficult to sort through those wires with nothing to reference from. (no connectors or pinouts). When i did mine I had to use a multimeter and using continuity find which wire went where. and either removed it or label it. I cant imagine how difficult that would be with out the pcm connectors and the pinouts. for example: locate pinout #26 its the tan wire from the blue connector. Thats the problem You dont know which of the 20 plus tan wires is the 26th pinout, let alone which is from the blue connector. Age has nothing to do with it. Can it be done? Yes. Should it be done? probably not. spend your time and effort somewhere else.

[Jonboy]

If you really, really want to do a harness, I have a stock one from an '01 5.3. I would sell it for $150 shipped. Check www.lt1swap.com for good wiring harness modifciation diagrams and instructions, too.

[hatzie]

Pick your battles carefully. It can be done. Will it be reliable? That's another story.
I've repaired terrible hack ups on far simpler engine and chassis harnesses. Then I repaired one or two splices again after a year or two of service and a few more as time went on.
Solder joints will make the copper brittle. Field installed crimp splices fail in interesting ways too. Neither splice method will flex like the original unmolested wire.

If you're attached and employed it's not a good use of your time... or your woman's patience.

Find an LS harness that isn't hacked to pieces by the yard monkeys. Then carefully label and pull it yourself. Lay it out and carefully strip it down to the essentials.

That 70 year old guy prolly has a good supply of patience. You'll need some.

[chevybuilder18]

Originally Posted by mrhino

It sounds like you are determined to do this, I admire you for that. However when you have several people who have done this swap telling you you should look for another harness either stock or aftermarket. you should listen. I dont think anyone on here is trying to talk you out of taking this on. Its just You asked the question and wanted real feedback from people who have done it. And that's what your getting. I agree with firebirdjones and others. It will be very difficult to sort through those wires with nothing to reference from. (no connectors or pinouts). When i did mine I had to use a multimeter and using continuity find which wire went where. and either removed it or label it. I cant imagine how difficult that would be with out the pcm connectors and the pinouts. for example: locate pinout #26 its the tan wire from the blue connector. Thats the problem You dont know which of the 20 plus tan wires is the 26th pinout, let alone which is from the blue connector. Age has nothing to do with it. Can it be done? Yes. Should it be done? probably not. spend your time and effort somewhere else.

Your probably right, and i agree. it would be easier to do all that stuff, sounds very easy. no offense to those who want me to head there advise, once im intrested in something my minds set. trust me firebirdjones you will not see any black tape here

[chevybuilder18]

Originally Posted by rfmaster

You can find wiring diagram at LS1tech.com (you'll have to sign-up for user id) - it is do able despite naysayers.

http://ls1tech.com/forums/conversion...schematic.html

/?RF

thank you for the link.

[chevybuilder18]

Originally Posted by Jonboy

If you really, really want to do a harness, I have a stock one from an '01 5.3. I would sell it for $150 shipped. Check www.lt1swap.com for good wiring harness modifciation diagrams and instructions, too.

thanks ill surely do that

[chevybuilder18]

Originally Posted by hatzie

Pick your battles carefully. It can be done. Will it be reliable? That's another story.
I've repaired terrible hack ups on far simpler engine and chassis harnesses. Then I repaired one or two splices again after a year or two of service and a few more as time went on.
Solder joints will make the copper brittle. Field installed crimp splices fail in interesting ways too. Neither splice method will flex like the original unmolested wire.

If you're attached and employed it's not a good use of your time... or your woman's patience.

Find an LS harness that isn't hacked to pieces by the yard monkeys. Then carefully label and pull it yourself. Lay it out and carefully strip it down to the essentials.

That 70 year old guy prolly has a good supply of patience. You'll need some.

haha i think he did