oxrabidus

I am looking for the enigne bay wiring harness for my 1985 camaro, it has an l69 305 in it.
The guy i bought it from messed up the wiring big time.

i am looking for a new one preferably. i also cant find a diagram for the harness im trying to find.

its the wiring that comes from the plug that comes out of the firewall on the driver side. the right side of the plug that has the starter, alternator, and sending unit wires all on the same plug. i have asked hawaks to see if they had some and they said they didnt.

if anyone knows where i can get one id really appreciate it.

thanks

jtsk

iTrader: (3)

You might try Painless Performance Products, but it will probably be pretty pricey.

oxrabidus

i tried painless all they have for third gens are fuel injection harnesses.

i may just suck it up and try to fix the one thta i have... but there are so many cables that are the same color... anyways if anyone knows where i can find a diagram for the plug that comes out of the firewall on the driver side id appreciate it ive spent days trying to find one...

thanks

Pocket

iTrader: (24)

https://www.thirdgen.org/forums/post...009-post4.html

Additional info has the diagrams you're hunting. How to prep shows how to convert an EFI harness to carb like you're doing now

Find a V6 harness in a junkyard and modify it to suit. You wont find a new harness for a carbed 3rd gen anywhere. I can link PNs and info about building your own with new parts if needed but no one sells them pre-assembled

83C_CamAroZ28

iTrader: (12)

try this guy...

http://berlinetta.info/wiring.htm

Jt41z4nZ28

^^how reliable is this site? It seems too good to be true haha.

Brando5641

iTrader: (-1)

Are you running a bare bones set up? no emissions?

Jt41z4nZ28

I wish!! Haha Ca smog laws require all that bs and its my daily driver. So to answer your question, no, i have my emissions equipment in there.

Jt41z4nZ28

I could remove it, then reinstall when i go to smog.

83C_CamAroZ28

iTrader: (12)

ive bought from him b4 he is a member on here.

im saving up sum cash to buy a harness also.

sonjaab

Try www.thirdgenranch.com
Shoot Denny a e-mail and see if he has one.

Sure its gonna be used.......... but un-butchered and complete!
Very reasonable $$ too !

T_Choat

I'm having kind of the same problem but my wiring harness got ate up by rats
I've looked everywhere so hopefully you guys saved me

rusty vango

call bruce at hawks they have what you need

Kes1907

Hi Guy's.

I am in the same trouble. The PO has butchered my L98 engine harness so badly I do not think I can work out how to rebuild it!

I was hoping to get a complete one somewhere. Obviously GM no longer have the right one for my vehicle PN 12068350.

I can however get a NOS one but the PN (12067691) comes back with an 88 car? Mines an 87. Does anyone know what the differences are and if it will fit?

FRMULA88

The bulkhead fitting thru the firewall is the same 82-92 and it connects directly to the fuse block.

you will just have to re-pin the connectors in the engine bay that plug into the bulkhead fitting.

All you need is the wiring diagram and new metri-pac connectors.

You can buy the metri-pac connectors at most auto parts stores. They comes in various sizes, but the f-body bulkhead uses 2 or 3. The largest of course for the ignition circuit most all the others are same size connector.

The crimping tool you can buy online.. it's not cheap but does a perfect OEM crimp.

John in RI

iTrader: (167)

Try Me,......... You will not be disappointed. oxrabidus; I should still have the correct Engine harness for your ride ( L69 with electric fan ) as well as the correct ECM harness if needed.


TO BE VERY CLEAR;

The C100 firewall bulkhead connector is NOT the same for all 82-92 cars. Will any C100 harness plug in; sure. Will it work,... only if you've got the skill, ability and tools necessary to add / remove/ modify it to work properly.

The only reason re-pinning would be needed is if you obtain a harness that is not compatible with your car. The Engine harness doesn't plug into the fuse-box,... It plugs into the dash harness. Sure - all C100 connectors "fit" together, but some harnesses will not have all the required circuits and others may have circuits that are not needed. ( Examples are wiring for electric fan and electric Speedo ). There are also at least 4 different wiper systems used in our Thirdgens,......each uses different wiring.

Kes1907,... The 1987 and 1988 ECM harnesses are NOT the same. Your 87 has an ENGINE harness and an ECM harness. In 1988 a single ( HUGE ) harness was introduced that included all teh under hood wiring. Be sure to ask for the correct harness when buying a replacement to avoid problems. Your ENGINE harness plugs into the drivers side firewall and the ECM harness ( passes thru passenger fender rail ) plugs into the ECM.

Kes1907

Hi John,

Thanks for the info. I am "restoring/repairing" an '87 IROC 350. It has had a small engine bay fire - due to an incorrect battery fitting I think -

The PO has had a go and made a real mess of it. It looks like he has tried to splice several differnent harness' together as well as his own connections and wiring and I am really struggling to work out what should be there and what shouldn't.

It doesnt help that he also deleted the AC system and some of the EGR/Carbon Catcher Can parts, So I have alot of plugs sitting around and I'm trying to work out what they attach to?!

My thought process was if I sourced a complete correct harness I could just do away with all his mess and effectively start again.

My biggest problem is I am an American living in the UK and we didnt have Camaro's over here so I can get no help/parts/info from any auto parts store or GM dealer.

As I said previously I found an '88 harness that was NOS but I'm now resigned to that being another closed door.

I am still waiting for a workshop manual and wiring diagrams to be delivered from the US so I may get some enlightenment there

FRMULA88

TO BE VERY CLEAR;


Kes1907,... The 1987 and 1988 ECM harnesses are NOT the same. Your 87 has an ENGINE harness and an ECM harness. In 1988 a single ( HUGE ) harness was introduced that included all teh under hood wiring. Be sure to ask for the correct harness when buying a replacement to avoid problems. Your ENGINE harness plugs into the drivers side firewall and the ECM harness ( passes thru passenger fender rail ) plugs into the ECM.

[/QUOTE]

WRONG !

The C100 does in fact connect to the fuse block.

I own a '88 and does NOT / did NOT have a single huge harness. My 1988 has / had an Engine harness and ECM harness routing as you described,.... I ought to know I rebuilt my engine harness 15 years ago after a "professional shop" tried to repair the ignition circuit without fusible links and the car almost burned! This same shop failed to find the actual short in the circuit,their solution was to remove the fusible link. Called me a week later and said the car was done.. LESSON LEARNED.

SO to solve the problem I took an engine harness from an '85 camaro I found in the junk yard . I also took the entire body harness from a 1989 Formula (mine was damaged) The body harness included the C100,fuseblock, and all connections ( fuel pump, power windoew, dash, etc)
using my original engine harness I re-pinned, the engine harness connector 1 wire at at 1 time. the fuse block and C100 from the '89 was a TPI car. so I swapped my TBI fuseblock and re-pinned the C100, again 1 wire at time.


I removed the ECM harness in 2000 when I converted to Holley projection on the 383.

I cleaned up the wiring again when I converted to carb a few years ago on the 421.

I know it can be done, because I did it. All you need is patience, the right hand tools and the wire diagrams for reference.

It was do it myself or pay another shop that wanted 1000$ just to get started... I think all in I spent 200 $ for the parts at the boneyard, solder, etc. This was back in 1994 I was younger man with alot of free time, but I learned ALOT about this car in the process.

Even now when faced with a problem I tell myself "If I can rewire an entire car and getting running again, I can do this too!"

sofakingdom

iTrader: (1)

John is exactly correct: C100 DOES NOT connect to the fuse block.

You can remove the fuse block separately from the interior side of it. 2 screws & 2 clips if memory serves. It will move quite a distance, on its separate pigtail.

John is also correct, that while the connectors "fit", the wires may or may not be the same. Different cars in different years had all manner of minor detail differences. For the most part, the same wires are there, they may just be in different "cavities". Sit down and think about it... all cars have temp sensors, oil pressure sensors, ignition, and so on. It's not too tough to take one KNOWN GOOD side, the interior side for example, and move the engine side wires around to match. Fortunately the L69 & LG4 engine side of it are virtually identical; might even be identical since the things that are different (electric fan, knock sensor in some years, etc.) don't pass through it.

Wiring is one of the easiest parts of a car to get right. Never ceases to amaze me how people get frightened of it. It's just not that hard. As was also said, some junkyard scraps, a bit of solder, heat shrink, crimp connectors, bear s***, and so on, can make one as good as or better than new.

I would try to do this with a harness from a different vehicle of about the same year with a similar engine (e.g. Caprice w LG4) before I'd try it with one from the same model of car but many years different. Above all, I would avoid the MAJOR design overhaul when they went from 2 discrete harnesses to one integrated one. That's biting off more than you can chew.

John in RI

iTrader: (167)

All 82-87 V8 Cars used 2 major harnesses, The Engine side and the ECM side. There are also independant Headlight and heater harnesses in all 82-92's.

All 82-85 V6 cars used 2 underhood harnesses. 86+87 MPFI used 1 large harness.

ALL 88 + cars use a single large harness under the engine bay. The Engine side and ECM side were integrated into 1 large harness and the wiper wiring was moved from the engine side of C100 to the headlight harness side of the C100.


Your car must be something specail or custom built because NO factory built 88+ Thirdgen has 2 seperate engine bay harnesses; NONE.

Kes1907; Although all 82-87's have a seperate/independant Engine harness ( except 85-86 V6 MPFI ),..... the engine harness for an 87 V8 is not completely similar to earlier years. ( Stay away from 82-83 Engine harnesses because of wiper compatability problems ! ) The 84-86 Engine harness plugs into (and wires are a direct match @ C100 ) but in 87 chevy used a re-designed Alternator, a remote Coil and a 'small cap' distributor. That means all those V8 engine side connections are specific to 87.

I've got a spare 87 Engine harness; I don't have the 87 ECM harness.

John in RI

iTrader: (167)

Virtually, but,......

HO cars were the first to get an electric fan and that wiring is run thru the engine side from 84-87 (C100@G7). LG4 cars didn't get an electric fan till later. An 83 HO harness will have the early "specific" wiper wiring too. Berlinetta LG4 harnesses were also different than all others because of the different wiper motor + speedo circuits. Thankfully, the ESC system (All HO and 85+ LG4) was in the ECM harness as you mentioned.

Just asking for an LG4 harness to replace a hacked engine harness in someones 83 HO could get them an 84 Berlinetta harness. That's why I try to promote being real careful / very specific when shopping around !!!

rusty vango

the one thing that will help you the most is a factory service manual. I got mine from "helm inc" they come with everything you need to know about the wiring. except the guts and patience of course.

Kes1907

Thanks Rusty,

I have ordered that same book (the official 1987 GM one). I'm just waiting for it to be shipped from the states. Although I ordered a digital copy on a CD as USPS wanted over $65 jost for shipping as the hard copies weigh over 5lbs

Hopefully when it arrives I may be able to make sense of the mess I have here and repair what I have.

Just in case I cannot...... John....the engine side of the harness you say.....? How much are you looking for? Is it complete with all the plugs? What does the engine side actually connect to in terms of sensors, ancillaries etc?

Kyle

John in RI

iTrader: (167)

I thought I had a picture of the 87 TPI engine harness, but can't find it ATM. For reference: ( your 87 is similar to the 85 )

This is an 85 Z28 TPI ENGINE harness : (Has C100 connector only )


This is an 88 Z28 TBI ENGINE $ ECM harness. ( Has C100 AND ECM connectors )



I really doubt that the existing Engine harness is what is causing the issues you describe. The 87 V8 Engine harness has all the wires that a NON fuel injected car would need to run. Power distribution, Starter, Alt, Distrib., Wipers, Coil. and Gauges. Many time the Fusible links degrade and that seems to be the most common reason for replacement.

The 87 TPI ECM harness is probably the one you are searching for. That one has all the engine data sensor connectors as well as connecting to the ECM itself. Some of the plugs on this harness are prone to turning brittle ( Fan sensor plug, knock sensor plug, Injector plugs, ect... )

Kes1907

Wow John, thanks for the pictures....think it will help alot....I really struggle to find reference material over here at the moment.

I am currently working nights and its been pouring during the day so I havent had a chance to pull the loom out and have a real good look at it.

We removed the whole engine from the bay with the loom still connected to it as I didnt want to mess the injector sequencing until I had a chance to label it.

I will hopefully get a chance over the weekend to detach it from the engine and photograph it in detail and compare it to what you guys have described.

If I cannot sort it myself I may post some pictures up so hopefully someone may be able ot point me in the right direction. Would you mind keeping an eye on this thread maybe early next week and at least identify what I have got or what is missing.

Sorry if i seem a little vauge. I've only had the car a week and I'm still VERY new to this. Especially the differing in model years.

American automotive is very different to British built stuff. Essentially over here they do not really change things from one year to the next. A car part will fit every model year of that production. They only really change things when they change the models completely - none of this year on year changes.

Kes1907

Hi John,

We had a few mins of sunshine on Friday so I managed to pull all the mees out from off the motor and photograph it.

Rather than clutter this thread I started a new one here..............

https://www.thirdgen.org/forums/tech...ml#post5738852

If you have a few mins spare one day would you mind having a look and telling me what you think?

I am new to this whole Camaro scene and am still trying to learn so sorry if I seem pretty dumb so far, my background is medical rather than mechanical but I am a quick learner.

Thanks

Kyle