I originally titled this thread, "How to disconnect C207 connector." The "connector" that this thread is about is not the C207 connector but rather a pass through of major wires coming mainly from the ECU but includes wires coming from the actual C207 connector. The actual C207 is shown in the second picture of post #2 by ratfink6923. It's the white connector seen by his foot in the picture. I'm going to go through this thread and try to edit it (including the title) so that actual misinformation isn't allowed to roam the internet. Obviously I won't be able to edit ratfink's posts.


I'm LS7 swapping my 1987, 350 TPI IROC. The TPI engine is out and now I'm trying to remove all of the wiring out of the engine bay in preparation for paint. I know that I won't need any of the TPI engine wiring since I'll be using a Holley Dominator.

I can't figure out how to take the pass through connector apart. Here is a picture of the connector on the passenger side of the car just forward of the door:



It's easy to see the locking tab on the side. I tried to unlock that tab but it didn't seem to do anything. I put a small mirror below this connector to see if there was anything on the bottom. I did see something. It looked like a hole with a bluish colored piece of plastic in it. I had no idea what to do with that. I need to get this connector apart so that I can get rid of all of this wiring in the following two pictures.


The bundle of wires in this loom that I'm pointing to go down to the pass through connector. Here are all the wires that I want to remove from my engine compartment. I know that I'll have to look closely at all of those wires because there may be some that I want to keep for my LS7? Holley Dominator swap.


Right now, I just want to get the pass through connector apart so that I can remove this giant harness from the engine bay.

 

The wires are potted inside, and not designed to split in two. If you go to the interior side of the connector behind your kick panel, there is a metal retaining clip that secures it to the body. Remove that, then push the tabs on to release. Be aware. That harness goes to the ECM connectors and a third connector that drives gauges and provides power. Im going to attach pictures of the connector body

 

Mind the bare feet. I was unwinding on the couch.

 

ratfink, thank you for your information and the pictures. So the pass through "connector" is not really a connector in that it can't be separated, right?

Earlier today, I was under the dash and I could see the bundle of wires going to the ECU. That shouldn't be a problem unhooking them from the ECU. Is there any special trick to unhook from the ECU?

I also noticed the other wire "branch" going to the gauges. How far toward the gauges will I find the white plastic connector in your second photo?

 

I was so focused on the wires and the connectors that I didn't even notice your feet !

 

Once out of the car, it can be separated, but the potting material will remain. My donor floor pan had the connector with wires cut on both sides, so I soaked it in gasoline over night and dissolved it to reuse the connector on my build. It has 50-60 wire capacity and is an existing passthrough.

The gauge connector is about six inches further in. To be honest, I had my dash out before I pulled my harness, so I can't help you with a location.

 

Disconnecting from the ECM is easy. Pinch to release and pull.

 

This is very helpful! Thank you.

 

Very helpful as well. Thank you! Thank you!

 

I just re-read your post. Are you saying that the connector can be separated outside of the car? I'm guessing the potting material is like a cured epoxy and gasoline was able to dissolve it. Once it was all cleaned up, did you buy new terminals (pins?)

 

Outside of the car, it can be separated with some patience and swearing. There are no terminals present in that connector. The wires remain whole as they pass through, and the separator comb is open on one end to allow them to drop in.

 

OK. There are no terminals inside that connector. Maybe Chevrolet wanted the 100% integrity of complete wires without crimped terminals from the ECU to their respective parts.

It's going to be a while before I have a chance to work on this car again. When I do, I'm going to remove the entire harness and use my 1987 Camaro electrical shop manual to figure out which wires I'm going to keep and which (most of the ECU wires) I'm going to leave out.

 

I'm in the process of doing the same with mine. I'm retaining gauge functions, and utilizing the ignition switch power leads in that third connector.
Best of luck with your project! If I remember to do so, I'll add pictures of what circuits I decide to keep from my harness.

 

Thank you and that would be great if you post pictures.

I've purchased a Holley EFI 12.3" Pro Dash that I'm going to somehow install in my IROC so I won't be using the stock gauges. I've got the same Pro Dash in my LS376/480, Tremec T56 Magnum swapped 1991 Foxbody Mustang coupe. It's so slick. It communicates with the Holley Dominator via a 2-wire CAN bus. The amount of information that it can be programmed the display is mind boggling. Among other things, I have it displaying my Corvette C7 PWM radiator fan's speed. They're pricey but not only are they super cool but the the PD eliminates a lot of the underhood wiring in that It gets all it's information from the Dominator which is already wired to all the sensors under the hood.

 

I was able to do this and it disconnected easily.

I'm still trying to disconnect the other branch that goes to the gauges. I either don't know how to do it or it's just difficult. I don't want to break the connector nor the locking tabs

 

I'm trying to push the pass through connector out of the car. With the plastic surrounding it, there is no way to push it out. I'm thinking this plastic surround needs to be removed. I guess I'm a dummy because I can't figure out how it comes off. Here are a couple of pictures of what I'm dealing with.


The screwdriver is pointing to a tab at he bottom. There is no way to squeeze this or push it up to allow the connector to go through the sheet metal.




So I thought that maybe I could just remove this entire plastic surround. The screwdriver is pointing to a locking tabs that holds the top half to the bottom half of the plastic surround. I pried these locks apart and the plastic surround still won't come off. It's like it's actually molded/glued to the pass through connector.

 

I got it out!!!!


It required tilting the pass through connector upward toward the red cable. I then was able to push on the big locking tabs on the bottom of the connector and the entire thing pushed through the square hole in the sheet metal.


Now its time to work the ECU and gauge connectors through the square hole and up into the engine compartment so I can remove it all from the car.