Powering my 84 C10

[coyotes33]

Alright folks i've been doing my swap in the shadows but now i really need some help with the wiring. I got my harness from PSI and installed all the engine section. Does anyone have a diagram of how i need to power the harness to the TCC, Ignition, alternator, battery to starter and what size wire i need to use? Im a newbie to all this so any advice will help.

[Clyde65]

That should all be stock, whatever you had there before the engine went in. and also the PSI harness should be labeled to what you need to connect to it.

Have you called PSI? They are really nice and good at helping.

[85burb]

I have a psi harness and mine came with a instructions. Give psi a call and they will help you.

[coyotes33]

Yeah the instructions seem pretty straight forward but since this is my first time doing something like this its some what intimidating. Plus the engine section was not labeled correct and didnt match the instructions.

[85burb]

I hear ya on the miss labeled motor connections. My harness had the maf connector by the alt. called and they sent me a extension for free. I just kinda winged it on the motor connections. The cab side of the harness was a bit funny as well. Like I have two browns and one is for ignition power and the other is check engine light ground. I like the harness but they need to redo the instructions.
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[coyotes33]

Need to figure out what goes to the starter, alternator and battery, any help?

[BR3W CITY]

Ok this is me being cynical as usual but its a blurry picture of 4 non-labeled redish wires in your engine bay.....how could anyone know that?


Here is a simplified ignition/starter circuit from Chucks chevy page, not exactly super technical but illustrates the idea easily.
http://www.chuckschevytruckpages.com...oodwiring.html

Where are the other ends of those wires going to? and (even if they are mislabeled) what do the instructions tell you? Everyone with a different swap harness on here will have different wires, even more so since some of us started with different stock wiring or no stock wiring at all.

[Clyde65]

what he said^^^^^^^^^


Ill also put this in there. the truck wiring is not molested much at all, put it all back the way you had it. remove from it only the stuff you wont use like the coil wire etc. the starter wires should all be like stock.

The PSI harness should be plug everything in and you should have about 5 wires to hook up. Call PSI and ask for ..John I think it is. they have great customer service.

[coyotes33]

They are coming from the block on the firewall. Thanks for that link.

Originally Posted by BR3W CITY

Ok this is me being cynical as usual but its a blurry picture of 4 non-labeled redish wires in your engine bay.....how could anyone know that?


Here is a simplified ignition/starter circuit from Chucks chevy page, not exactly super technical but illustrates the idea easily.
http://www.chuckschevytruckpages.com...oodwiring.html

Where are the other ends of those wires going to? and (even if they are mislabeled) what do the instructions tell you? Everyone with a different swap harness on here will have different wires, even more so since some of us started with different stock wiring or no stock wiring at all.

[coyotes33]

Yeah i emailed Jon and he just referred me back to the instructions that come with the harness.

Originally Posted by Clyde65

what he said^^^^^^^^^


Ill also put this in there. the truck wiring is not molested much at all, put it all back the way you had it. remove from it only the stuff you wont use like the coil wire etc. the starter wires should all be like stock.

The PSI harness should be plug everything in and you should have about 5 wires to hook up. Call PSI and ask for ..John I think it is. they have great customer service.

[85burb]

The psi harness don't have any wires for starter and alt charge. That stuff will be factory. Did you get all the sensors plugged in? If you have questions about some of the connectors you have take a pic and post them and I may be able to help you figure out where they go.
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[coyotes33]

Thanks, i figured all the connections out. I just need to do the dash wires.

Originally Posted by 85burb

The psi harness don't have any wires for starter and alt charge. That stuff will be factory. Did you get all the sensors plugged in? If you have questions about some of the connectors you have take a pic and post them and I may be able to help you figure out where they go.
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[coyotes33]

So the original purple wire goes to the alternator. What about the red wires that use to go to the old starter? Do i have to hook those up any where?

I still have the positive wire that goes from the starter-> red box->battery and negative from the block->battery. I still need to a ground from the block->frame and block->body. I'm i missing anything?

[mej005]

Double check this diagram:

http://www.73-87chevytrucks.com/tech..._V8_engine.jpg

One goes to the starter and one to the junction block (number 2 on the firewall connection) and you should have to run a wire from the starter to the junction block on the firewall and from the alt to the junction block. I had to hook all of those up in order to have 12 volts inside and outside the cab. If you need some more info let me know; I just did this 2 weeks ago.

[coyotes33]

Ok so you ran one wire from the starter solenoid to the juction block or two coming from the battery connection? The other one goes from the bolt on the starter to the junction block.

QUOTE=mej005;5948817]Double check this diagram:

http://www.73-87chevytrucks.com/tech..._V8_engine.jpg

One goes to the starter and one to the junction block (number 2 on the firewall connection) and you should have to run a wire from the starter to the junction block on the firewall and from the alt to the junction block. I had to hook all of those up in order to have 12 volts inside and outside the cab. If you need some more info let me know; I just did this 2 weeks ago.[/QUOTE]
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[mooseknuckles]

I removed that fire hazzard block thingy from the firewall, and used one of the heavy gauge wires from it for 12v to the pcm, with an inline fuse of course....another wire goes from the starter to the alt. the heavy purple starter wire goes back on the starter...I used the heavy pink ignition wire that used to go to the distributor to turn on the pcm...

[coyotes33]

So if i keep the junction block can i run a wire straight to the pcm relay from the alternator for the constant 12v? i need to run a wire from the starter solenoid to the alternator? And you hooked up the small red wire from the pcm relay to the pink ignition wire?

QUOTE=mooseknuckles;5950469]I removed that fire hazzard block thingy from the firewall, and used one of the heavy gauge wires from it for 12v to the pcm, with an inline fuse of course....another wire goes from the starter to the alt. the heavy purple starter wire goes back on the starter...I used the heavy pink ignition wire that used to go to the distributor to turn on the pcm...[/QUOTE]
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[mooseknuckles]

just run a fused wire from the junction block for the pcm's 12v.....I wouldnt use the alternator for that.....the alt needs to charge the system, I think the wire originaly ran from the alt to the junction block....the original pink distributor wire, a 12v ign. to the pcm...use a test light to double check..

[coyotes33]

Im still a little confused on what wire to run from alt to starter. Are you saying to run the wire that use to go from the junction block to alternator?

Originally Posted by mooseknuckles

just run a fused wire from the junction block for the pcm's 12v.....I wouldnt use the alternator for that.....the alt needs to charge the system, I think the wire originaly ran from the alt to the junction block....the original pink distributor wire, a 12v ign. to the pcm...use a test light to double check..

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[mooseknuckles]

It's been awhile but IIRC my truck had a wire from the alt to the junction block and from there it went to the starter....I eliminated the junction block, so the alt wire now goes to the big terminal on the starter...

[coyotes33]

Alright, well since im keeping the junction block i should follow the diagram in the link provided. Wire from alt to junction block, junction block to starter, original purple wire to starter and pcm to junction block with fuse.

Originally Posted by mooseknuckles

It's been awhile but IIRC my truck had a wire from the alt to the junction block and from there it went to the starter....I eliminated the junction block, so the alt wire now goes to the big terminal on the starter...

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[coyotes33]

On the PSI Harness theres two brown wires listed on the instructions, one is dark and other is light. Does anyone know which one is which?
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[coyotes33]

Disregard the question above, seems psi changed colors but not their instructions. I have another issue now, it seems my fuel pump is not turning on. Should I be getting 12v with the key on? If I should im not and when i add constant power it turns on. Any suggestions?

[mooseknuckles]

one is the mil lamp and the other is a switched 12v, power on with key and cranking.... the fuel pump should be wired into the relay...shows in the instructions...http://psiconversion.com/tech_articl...structions.pdf

[coyotes33]

Ok i have everything hooked up. I have constant 12v to the relay and 12v to the ignition on/cranking. My fuel pump is not turning on so the injectors aren't spraying and it does turn over. I have checked all my connections, what else can i do to check that the pcm is turning on?
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