i put an ls1 into my 93 pickup i got a stock 2001 engine harness what wires do i need to hook up to make it run other than common stuff like the injectors and sensors. also what color are these wires i know i nned the main power wire for the computer and the ignition wire which i dont know what wires this is. all the help will be helpful thanks kenny heaverin

 

That's a pretty big question. The PCM uses two 12VDC feeds, one fulltime and one ignition-switched. You have gauges, fans, fuel pump, fused voltage to the injectors/coils, and others.

You have three basic options to choose from:

1.) Send your harness to someone like Speartech for simplification. You'll get it back with four or so wires to connect to your chassis, clearly labeled. Costs $$.

2.) Buy a Helms manual for the '01, maybe one for your '93 truck also, and map it out yourself. Costs less $$, but much more time.

3.) Post here and hope for the best.

Speartech gave me free advice when I was doing my swap, so I'm not going to pay him back by taking business away from him.

No problem answering detail questions like "where did you get the pins" type stuff, or helping troubleshoot.

 

so this is going to be a big pita for the wiring it up to run

 

How much of a PITA depends on how good you are with wiring schematics.

It took me most of a Saturday to write up the engine harness, then map each pin to the right place on the chassis harness, 12VDC, fan relays, fuel pump relay. 5 pages of notes, connector by connector on the LS1 side {C100, C101, C105, C207...} then connector by connector on the chassis side {C207, C100}.

Then another day or so of measuring the needed wire lengths to hit each connector source and target, and fabbing a translation harness...no cutting of either the engine or chassis harness this way. $40 eBay junker '00 chassis harness had everything I needed except crimp pins...nice TXL wire in the right colors and gauges, conduit, connector hoods.

 

If you are keeping your stock pcm off the 93 make sure that you run another hot wire(one that turns on with the key) to your fuel pump relay. What transmission are you using? If you have any questions just pm me. I put a 5.3 into a 94 chevy truck

 

Call Fuel Injection Specialties in San Antonio Texas. Send them the underhood harness from your truck and the harness for the 01. They charge about 250-400 but when you get it back it will be set up for the ls1 and your 93'. It will plug into the firewall bulkhead and snap into everything on the ls1 with no guessing. We have taken this route at the shop and done several ls1 conversions using their harness. I can do all of this myself but when it is not my own stuff I cannot justify my time to do it, when we can pay them and get a turnkey harness that I do not have to tinker with.

 

see i am running low on the conversion money i only have like $150 left for it. I got rid of all the factory wiring and computer. i am running aftermarket gauges a switch for the fuel pump with a relay of course. I mainly need to know which wires to hook up to get it running and the colors of them and where they go. also does the engine harness need a fuse block or anything like that i didnt think it did but maybe i am wrong thanks for any help

 

I can get the info tomorrow at work along with the exact pinouts and locations. All gm pcms just use a couple of 12v cns inputs and two or three switched ignition. I did not realize you had already done all of that. The ls1 pcm and oil pressure switch can control the stock fuel pump unless you just want a switch.

 

great you are the man. See my goal is to have it done before my brother in law ships out to iraqi for a 1 1/2 years he wants to see it run. thanks so much kenny also i am running an aftermarket inline pump

 

I used fusible links for the underhood voltage feeds, couldn't find a weather-resistant fuse block I liked at the time.

Here's a list from memory:

1. 12VDC to underdash fuse panel
2. 12VDC to PCM
3. 12VDC to fan relays 1 and 2
4. 12VDC to fuel pump relay
5. 12VDC to passenger compartment

The rest of the voltage needs are supplied from the underdash fuse panel...injectors/coils, PCM switched, gauges, etc. These were already managed by the ignition key, so it worked out nice.

 

since i am running a diffrent fuel pump and diffrent fans do i need to hook those 12vdc up or not. do i need a fusible link in them? what colors are those wires you named off? where would it hook up in the passenger compartment and what for? thanks

 

The fan(s) and pump need 12VDC (fused, always) so if they're not getting it thru what's left of your existing chassis harness you'll need to fabricate feeds and relays so the PCM can control them.

The 12VDC feeds for these aren't part of the engine harness on F-body LS1 engines, they and the relays are part of the chassis harness. Only things related to them in the engine harness are the relay control wires from the PCM.

(Even if you use manual switches instead of the PCM to control these, you'd still want relays instead of running the full ~10A service feeds direct thru a switch.)

I fabricated the relay harness and 12VDC feeds as part of my built-from-scratch "translation" harness that connects the LS1 engine harness to my '82 Camaro chassis harness.

Each relay needs four wires...

12VDC in from fused batt+ source
12VDC out to fan or pump
switched 12VDC pull voltage for fans, ground for fuel pump
PCM control wire (PCM switches ground for fans, switches 12VDC pull for fuel pump)

 

we are putting relays in for the pump with the switch so why do inned the pcm wire for the pump hooked up if i am using a switch? Also the fans are on a manual fan controler bought from autozone they work fine come on at 180 degrees always. So why would i need these wires to have power to them or even hooked up if the computer doesnt need to control them? Or will the computer not work if i dont have these hooked up and the engine wont run? So i need the chassis harness off my camaro with the fuse block to run into the engine harness so the injectors have a fuse block or am i wrong? I am not to sure if i understand what you are talking about on the fuse block chassis part. I sound like a dumbass but not to good with this wiring stuff when it comes to fuse blocks. thanks kenny

 

If the PCM monitors the fuel pump relay control like it does the fans, it will throw an error code. Easy to disable this error code with LS1-Edit and the like.

Same deal as the fuel pump relay question, just need to disable the error code in software. I'm only using the Fan 2 control to manage both of my fan relays, just disabled the Fan 1 error code using LS1-Edit.


You could use the chassis harness and fuse/relay boxes, lots of extra stuff you'd want to remove (ABS, etc.). I figured it was easier just to build the translation harness in my case, using harvested wire and connector hoods from an '00 chassis harness I got on eBay. My '82 Camaro under-dash fuse panel already had fused ignition-switched feeds for injectors, computer, gauges, etc. so I just used them.

 

so on my truck fuse panel i have a ignition fuse so should i run my injectors and my computer wire to it?

 

That's your call. In making that decision, you'd want to look at a schematic, what gauge the wiring feeding that fuse is, and determine if it can handle the load that both injector/ignition circuits and the PCM will put on it.

On my '82 fuse panel it had separate fuses for INJ-1, INJ-2, and the ECM so I kept them that way for the LS1 feeds.

 

I got ya i will take a look at mine tomorrow to see what fuses it has my truck originaly was a350 tbi so it might be the same thanks i will let you know tomorrow

 

First off, GREAT thread... people actually helping people! Wahoo! I just wanted to jump in on this thread since I had some questions that relate to 12V feeds and whatnot... might help anyone else doing the same. I am looking at my PCM pinout chart and wondered about the following pins/wires...

Blue PCM Harness:
Pin 2, LT GRN, Crankshaft Position Sensor B+ Supply...
Red PCM Harness:
Pin 39, RED, Camshaft Position Sensor B+ Supply...

Are these wires SUPPLYING B+ to the crankshaft/camshaft position sensor or do I need to supply THEM with B+?

With the talk about feeding injectors... on my PCM pinout chart, I only see Injector 3 Control, Injector 2 Control... are these wires control "signal" wires that tell the injectors when to work (inject)? Or are these supposed to be feeds of some sort. Again, I don't see anyplace in the PCM pinouts where your supposed to feed injectors. I see Ignition and Battery Positive Voltage and have noticed by tracing some other wires through the harness that they are apparently junctioned within the harness because sometimes multiple PCM plug wires trace from the PCM plugs to the engine-chassis harness plugs... if thta RUN-ON sentence made ANY sense! lol

I am also curious... without going and buying a complete or partial chassis harness, is it possible to purchase the female plugs to mate to the engine harness where it would plug into the chassis harness? There are four plugs between the PCM and battery of the F-body which I would like to leave intact. If I could find females for them, I could build my OWN "transaltion" harness to use my Isuzu underhood fuse/relay/breaker panel.

Oh, and one more question while we are talking harness wires... there is a larger gauge PURPLE wire that has a single wire plug on it... one of the four engine-chassis harness plugs. I vaguely recall that at least in OLDER GM vehicles, the starter solenoid wire is a PURPLE wire... could this be the starter solenoid wire?

OK, that was plenty for now. I hope to hear back from some of the more hands-on experienced members. Just for the record, I am very capable of tracing and hooking up wires, I just want to make sure I don't accidentally feed/ground something that wasn't supposed to be... and in turn SMOKE my PCM. THanks in advance.

 

Why is it that when I post to a thread it dies! lol Anyway, I dug through my pile of spare parts from my old motor and have decided that I will be recycling my Isuzu underhood fuse/relay panel... there are nine mini-blade type fuses, 10 single-pole double-throw relays, along with five main breakers (ranging from 30A-100A). I have opened the case up and have started mapping out the wires to use for PCM and whatnot but have some questions.

I know I'm gonna have to feed the injectors and coils some juice. Where might I do that? I mean, what wires in the PCM harness get fed for those things? I'm assuming I can pick them up at the engine-chassis harness plugs. Anyone care to help a brutha out?

Thanks!

 

hey the starter wire is purple. thanks all you guys got the conversion running