Wires going through firewall?

[lil' jon]

I'm currently swapping an engine and transmission from a 97 Camaro into a 98 Firebird. I have the wiring harness from the Camaro's engine too. I'm a little stumped about what the three connectors going through the firewall do. They are different between the two wiring harnesses. I'm guessing they could go to the headlights, HVAC controls or ignition but I really don't know. Does anybody know what these wires go to? Here's a few pics of what I'm talking about:

This is where the wires connect inside the car:


Here's what the original Firebird connectors look like:


The Camaro's wiring harness looks pretty similar where it goes through the firewall with the exception of these 4 loose wires (didn't get the connector with the engine):


I'm assuming these should connect to another off-white connector like there is inside the cabin, but the number and color of wires don't match up.

Any help is greatly appreciated since I'm kind of stuck at this point of the engine swap.

[Tom Rs]

Re: Wires going through firewall?

the thick purple wire is the starter, that should be an easy find. Never saw that 2nd white connector before. If you can tell me the pinouts on that beige connector i can tell you what wires are what.

[lil' jon]

Re: Wires going through firewall?

oops didn't see this before I responded to your PM...
I'll go look at the pinouts now. thanks tom
oh yeah it's a 98 firebird

[lil' jon]

Re: Wires going through firewall?

I don't really know how to label pinouts and stuff so I just made this drawing, hope it makes sense haha.



...the black ones are not being used, and the purple shown here is much smaller than the thick purple shown above.

[Tom Rs]

Re: Wires going through firewall?

are there wires in my harness blue and white connector that have nothing to line up with on the car side ? have u found the starter wire yet ? maybe that beige connector is for something else. i dont have one on my car

[lil' jon]

Re: Wires going through firewall?

Hmm not sure, I'll take another look tommorow. Maybe the beige connector goes to the flip-up lights or something since those are firebird specific.

[Tom Rs]

Re: Wires going through firewall?

I am pretty sure if you line up the wires i talked about the car will run. Orange is pcm batt, Black is the fuel pump ground, anf the purple you cant miss.

this is the interface from the ls1, I am not positive what these mean, i can help you tomorrow.

[ssms5411]

Re: Wires going through firewall?

I would grab a Haynes manual it has great diagrams in the back for wiring for both 3.8 and LS1 engines.