I searched and searched, and couldn't find the answers I needed. I’m doing an ’94 Camaro LT1 swap into my ‘91 Firebird. I have wired up most of the wires, but could not find where the rest should go. I have looked at all the wiring digrams that I could find on here and in my Haynes manuals('91 and '94).

Here is what im stuck on:

On the white 10 pin C220 Plug (‘94 Camaro Plug)
A is RED and is Alternator feed to instrument cluster
B is TAN and is oil pressure feed to instrument cluster
C is BRN and is oil level feed to instrument cluster
G is DK GRN/WHT and is vehicle speed signal.

On the blue 10 pin C230Plug (‘94 Camaro Plug)
E is DK BLU and is theft deterrent - fuel enable feed

On the blue 4pin C210 Plug (‘94 Camaro Plug)
A is PPL and is ignition (crank starter) (connected to starter relay)
B is BLK/WHT ground
C is ORN power feed from ECM BAT fuse #4
D is Supposed to be empty by the diagrams, but there is a GRY wire in the location.

TBI fuel injection ECM connector (Clear Connector)

A8 ORN Serial Data (Could not find on LT1 Harness)
C9 PPL/WHT Crank Signal Wired to PPL A terminal on 4 Pin Black Connector (C210)?
B6 “Not Used” But I have a BLU wire in the location

*Also there are two BRN wires from the ECM that are not labeled in the diagram

Bulkhead C100 Plug (‘91 Firebird Plug)

A7 PNK/BLK Idle speed control (V8VIN H)
B4 PPL Starting System (starter Interlock)
D5 GRY diagram indicates Wiper/Washes (Note: D5 is actually PPL wire, came from ECM)
G5 Red Power Destitution (Light Switch, Fuse Block)
* There are also another PPL wire that I do not know where to wire, possibly E4 or D4?.

Any help would be greatly appreciated. Thanks.

 

Ok,

On the white 10 pin C220 Plug (‘94 Camaro Plug)
A is RED and is Alternator feed to instrument cluster I have mine wired to a switched source, this is what tells the alternator to start charging
B is TAN and is oil pressure feed to instrument cluster This will hook into the original C100 block which will goto the gauge cluster, don't know which pin right off hand though, but it will be a tan wire.
C is BRN and is oil level feed to instrument clusterIf you have a low oil light, this will goto the wire for it
G is DK GRN/WHT and is vehicle speed signal.I ran this wire to where the original yellow VSS buffer box was and tied it into the wire that goes to the speedo, it may be either light green or grey, possibly tan, the LT1 PCM puts out a 4000ppm signal so the buffer box is not needed unless you want to keep the cruise which I'm going with a 4th gen cruise module.

On the blue 10 pin C230Plug (‘94 Camaro Plug)
E is DK BLU and is theft deterrent - fuel enable feed This is the vats wire, if you have VATS programmed out, this wire is not needed. (btw you have a PM)

On the blue 4pin C210 Plug (‘94 Camaro Plug)
A is PPL and is ignition (crank starter) (connected to starter relay)I ran this wire down to the starter and put it on the little lug of the starter, works fine this way.
B is BLK/WHT ground This is a ground wire for the PCM, just ground it to the body somewhere
C is ORN power feed from ECM BAT fuse #4 This wire was not on mine, but in a different plug but this one is what keeps what the PCM has learned while you drive stored and the codes stored if any, needs to be hooked to a 12v constant like the distribution block on the side of the radiator support and fused.
D is Supposed to be empty by the diagrams, but there is a GRY wire in the location. Never figured this out since my LT1 harness didn't have a grey wire there, but the old plug I'm using did.

*Also there are two BRN wires from the ECM that are not labeled in the diagram Which plug are these wires in?

TBI fuel injection ECM connector (Clear Connector)

A8 ORN Serial Data (Could not find on LT1 Harness) If this is setup like mine, the serial data wire is a tan wire in the LT1 C100 plug.
C9 PPL/WHT Crank Signal Wired to PPL A terminal on 4 Pin Black Connector (C210)? You can do that if you want, I didn't bother with mine this way
B6 “Not Used” But I have a BLU wire in the location Not a clue

As for the C100 connector, the only ones you will really need are the fuel pump which will be grey, tan for oil, green for temp and white for tach, the rest will go through the C207 on the passenger side for ECM fuse, INJ fuse and possibly fans.

Hope this helps.

 

Here are the few remaining wires that I still can not figure out what to splice to.

White C220 Plug (‘94Camaro)
J Dk GRN/WHT is fuel pump relay control
F TAN, but the diagram indicates it should be GRY Fuel pump motor feed

*There is a relay on the drivers side, and one on the passengers side. Which is the fuel pump relay?


Clear Connector (C207?) ‘91 Firebird

Pin “A”: Air select valve (brown wire) do I even need this?
Pin “K”: VSS (brown wire) I’m confused about this one, because we have a brown wire in C207, and the yellow and purple wires labeled VSS going though C100 that go to the yellow buffer box. What do we hook up where?

Is pin J the serial data wire? What do we connect the wire to, because the LT1 C100 had no tan wire, there is a plug where it should be.

Pin “R”: (PPL/WHT) Three amp crank fuse, where does it go?
Pin “L”: (Blue Wire) is for the VATS?

C100 '91 Firebird
Pin "A7" : (PNK/BLK) Idle speed control. Do i need it?

 

Ok

White C220 Plug (‘94Camaro)
J Dk GRN/WHT is fuel pump relay control THis will goto your fuel pump relay green/white wire, that is what primes the pump and when the PCM tells the relay to fire.
F TAN, but the diagram indicates it should be GRY Fuel pump motor feed Not needed, at least I didn't use it I think this is the test wire for the fuel pump.
*There is a relay on the drivers side, and one on the passengers side. Which is the fuel pump relay? Fuel pump relay *should* be on the driver side, 5 wires, two orange, green/white, black/white, and a grey.

Clear Connector (C207?) ‘91 Firebird

Pin “A”: Air select valve (brown wire) do I even need this? No
Pin “K”: VSS (brown wire) I’m confused about this one, because we have a brown wire in C207, and the yellow and purple wires labeled VSS going though C100 that go to the yellow buffer box. What do we hook up where? The wire marked on the '94 harness as VSS output goes to the either the green or tan wire where the VSS buffer box is at, this will goto the speedo.

Is pin J the serial data wire? What do we connect the wire to, because the LT1 C100 had no tan wire, there is a plug where it should be. Some show a serial data in the white connector, possibly since yours is a '94 it is there, mine is a '95 and it was in the bundle with the C100 connector.

Pin “R”: (PPL/WHT) Three amp crank fuse, where does it go? If this is in the '91 harness, this goes to the starter through the C100 bulkhead
Pin “L”: (Blue Wire) is for the VATS? Possibly, shouldn't need it.

C100 '91 Firebird
Pin "A7" : (PNK/BLK) Idle speed control. Do i need it? No

 

These should help you out I hope

 

C100

 

C220 (the white one)

 

C230 (the blue one)

 

Thanks for the info so far, we almost have this thing licked. I have ran into a problem with identifying relays because none of the colors in the relays match the diagrams (in the manuals or here).

Relays I Have:

Drivers Side Relay:
Pin “E” (RED)
Pin “F” (GRN/WHT)
Pin “D” (BRN)
Pin “A” (BLK/RED)

Passenger Side Relay:
Pin “D” (ORN)
Pin “E” (PPL)
Pin “F” (BLK)
Pin “A” (RED)

I’m still unsure about the VVS wires. The brown wire is supposed to go to either the green or the tan wire, but I don’t have a green or a tan wire. Here is what I have.

My 4 Out Buffer: (yellow box)

Long Black Plug:
Pin “A” (BLK/WHT)
Pin “C” (BRN)
Pin “E” (RED)
Pin “F” (BRN)
Pin “H” (PNK/BLK)

Short Black Plug:
Pin (PPL)
Pin (YEL)

 

Ok

Drivers Side Relay:
Pin “E” (RED)
Pin “F” (GRN/WHT)
Pin “D” (BRN)
Pin “A” (BLK/RED) Pin E is actually an orange wire, or should be, this goes to the cooling fan.

Passenger Side Relay:
Pin “D” (ORN)
Pin “E” (PPL)
Pin “F” (BLK)
Pin “A” (RED) This is the blower motor high speed relay, not related to the engine running

My 4 Out Buffer: (yellow box)

Long Black Plug:
Pin “A” (BLK/WHT)
Pin “C” (BRN)
Pin “E” (RED)
Pin “F” (BRN)
Pin “H” (PNK/BLK) Pin C is the one you want to hook the VSS output to, that is the tan wire. Don't worry about any others.