Working on this GTA and the fan relay's by the front Right headlight housing have been cobbled with wire nuts and speaker wire! Looking through the factory manual to see if we can figure out what happened. Guessing a fan stopped working and the PO tries some sort of workaround.

Right now we have 3 Black wires with the red stripe all cut and we're not sure if they all attach together or not. Also the tan with white stripe wire looks to have 2 wires plugged into the same spot on the plug.

Finally, on the other side of the engine the green wires for the A/C compressor had some loose tape, When I pulled the tape there looks like a small resistor jumped across the pins. Never seen that before. Not sure if it is correct or not.

Can anyone help us out here? Maybe some pics of what these things are supposed to look like?

TIA

 

Strongly recommend acquiring the factory service manual for your year. You're going to need to go back and forth with the diagrams and what you are currently seeing in order to begin diagnosing what needs to happen to return to factory operation.

 

The attached pdf, is pages from a 1988 service manual and should be close. It hopefully helps.

 

The Air Conditioning Refrigerant Compressor Electrical Connector ABSOLUTELY requires that Diode that you found connected between the Two Terminals of the Connector.

It is a VERY important Component, do NOT disturb or remove the TVS Diode.

I will try to return with some 1987 Firebird schematics.

 

Thanks for the responses. We have the Factory manual with the schematics. It's sometimes easier to "visualize" when I see an actual pic of how the wires are run.

 

 

Well from those Images, there are a few issues that need resolving...

There should never be any "Wire Nuts" for Solid Core AC Electrical Wire being used to couple wires together.
Anything like that needs to be removed from all of the wiring, and some proper Splice or Connector needs to be used to re-join any wires.

Next, the Original Cooling Fan Relay Connector on your car is a known problematic Connector that should be updated to the GM Replacement Design or to another Aftermarket Design Connector and Relay.

Any Relays that originally used this type of Connector shown below, should be updated:


The Updated GM Design Relay and Connector are shown on the Left of the Image below:


And below is an Updated Wiring Harness for Dual Cooling Fans:


If you need some Part Numbers for Relays or Connectors, let us know.

 

Well crap. All my relays look like the bad ones. Ugh. Wasn't planning on replacing so much stuff. (Well, except for that hack job that was already cut out.) (We were guessing that one of the fans stopped working and someone hacked a work around but we are not sure) Are thee other problematic areas I should be tackling first or testing?

I will need all the part numbers, links, pricing. etc. So I can start addressing these problematic pieces.

I found that updated harness for the cooling fans for $80 on ebay. Maybe I should make my own or is there anyone else offering this service? I have the tools and we've recently been doing full AAW harnesses on a couple other cars. I'd like to not get nickel and dimed on this car for a few wires and relays if I can help it.

 

Post #11 and 12 have some part numbers for relay and connector.

https://www.thirdgen.org/forums/ltx-...e-4th-gen.html

 

Awesome thank you! Before I go all in and jump into this rabbit hole, are any of the electronic guru's here making these harnesses or updated bits so that they are a basic plug and play? It would be nice to just purchase what I need at a reasonable price so I can keep my project moving without having to stop and build or rebuild---

If harnesses are not being made/sold, is there a preferred site where all these electronic bits can be purchased or is it just the usual suspects (amazon and ebay)?

Update: OUCH! Just looked on Amazon for a couple of these part numbers. Did not realize how pricey these relays were...

 

Theres lots of crappy relays out there. A good relay is becoming more difficult to find. That updated gm relay in the pic was a good relay if you can find it. 95% of what you see on amazon is garbage. For my fans/ecms/fuel pumps i always use either fastronics or that updated GM one. The cheap relays always crap out or function inconsistently over time.

 

They would. They changed over to the ones with the sealed connectors in a later year, so your car has the older ones, consistent with its year. Like so many other things, we've learned, as a species, how to do things better over time, and those older connectors and whatnot, that are open to the elements, are something that hasn't stood up well to the test of long-term usage.

I'm pretty sure that's what happened, and I wasn't even there to see it when they did it.

You can get those relays from any number of people who make harnesses for EFI systems, since they're widely used for that sort of thing. You can make your own harnesses up easily enough: you can get TXL wire readily, and all the Weatherpak connector parts are available. Mouser seems to be the best source usually. www.mouser.com The brand name nowadays is Aptiv. Although, if you don't have the tooling and experience etc., as well as starting from scratch where you have to deal with stuff like buying a 50' roll of the right color wire to get 6", it's probably better to just buy the finished product from someone who does it on a regular basis. You can also pick up lots of that stuff, particularly relays and sometimes suitable pigtails, at the boneyard.

 

The Relay Design that I posted was the Delphi Metri-Pack 280/ 630 Hybrid/ Mixed Design.



There are other GM Design Relays as well as Aftermarket Designs too!

We have to make sure though that the Relay and Connector being used are intended for higher Ampacity/ Current demands.
So the GM ISO-280 (Delphi Metri-Pack 280 Series) should not be considered as its a lower Ampacity Design.




The GM ISO-630 (Delphi Metri-Pack 630 Series) should be a great option!
However it is a "Pull to Seat" Connector Design that is less than pleasant to assemble...
So I recommend the lesser known "Push to Seat" ISO-630 Design instead.

Here is the "Pull to Seat" that most all know:



And here are the "Push to Seat" Design:




The above Relay and Connector type would be what I recommend for you.

 

Thanks again for all the info. At this point I have quite a few irons in the fire with this car. Might be easier to simply buy a pre-made harness. Does anyone here have a recommendation on who to contact and what I should be expecting to pay?

Just want to button up this area while everything is apart.