I am getting ready to put my LT1 in real soon and I am going to save myself the $350 and do the wiring myself. I have 2 wiring harnesses to work with, one from a 95 A4 Vette and one from a 95 A4 Z28. The only problem is, I am going to keep my T5 until either it blows or I can afford a T56. (Hopefully the T56 comes first) Can someone please help me figure out which wires I will need to keep and which ones I need to switch over ? I also read in the "LT1 swap" posts that someone has wiring diagrams from a "Big book"? What does that mean, and can I get a copy of them ? Thanks for everything!!

 

Get the helms manuals for your third gen and the 95 ta or vette. They will cost you about 80 bucks each but are well worth the price if you are making your own harness. I didn't get them right away because I didn't want to spend the money. I finally broke down and bought them. I wish I had done it in the beginning it would have made everything much easier.
Kory

 

That's for a 93 camaro :

VATS 16 pin
|------------------------|
A8| [] [] [] [] [] [] [] []| A1
B8| [] [] [] [] [] [] [] []| B1
|------------------------|

Slot Wire Color Description
A1 Orn Power feed from ECM BAT fuse #4
A2 Pnk Power feed from ECM IGN fuse #5
A3 DK BLU Fuel enable signal
A4 YEL/BLK Starter enable relay control
A5 GRY "Security" indicator lamp control
B5 BLK/WHT Ground
B7 PPL/WHT Ignition key resistor return
B8 WHT/BLK Ignition key resistor feed

| | Top White 10 pin
|K|J|H|G|F|
|A|B|C|D|E|

K is DK GRN and is the coolant temperature feed to instrument cluster.
J is DK GRN/WHT and is fuel pump replay control
H is empty.
G is DK GRN/WHT and is vehicle speed signal.
F is GRY and is fuel pump motor feed.
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.
D is empty.
E is empty or if you have a manuel tranny it is the clutch anticipate signal and is GRY.

| | Top Blue 10 pin
|K|J|H|G|F|
|A|B|C|D|E|

K is TAN/BLK and is (Automatic) torque converter clutch control.
J is ORN/BLK and is (Automatic) park/neutral feed from transmission position switch.
NOTE: If this vehicle is manuel the wire would be LT GRN and would be (manuel) backup lamp feed.
H is LT BLU/BLK and is (Automatic) TCC switched power feed.
NOTE: If this vehicle is manuel the would be be BRN and be (manuel) power from turn B/U fuse # 2 to backup switch and would be brown.
G is PNK and power feed from ECM IGN fuse # 5
F is DK GRN/WHT and is A/C request signal
E is DK BLU and is theft deterrent - fuel enable feed.
D is WHT and is techometer signal to instrument cluster.
C is WHT/BLK and is diagnostic request signal.
B is service engine soon indicator feed.
A is empty.

Black Connector 4 pin
|A|B|C|D|
A is PPL and is ignition (crank starter)
B is BLK/WHT Ground
C is ORN Power feed from ECM BAT fuse #4
D is Empty

C100. It connected (on the 93) to the underhood fuse block.
|A|B|C|D|E|
|K|J|H|G|F|
| |
A is PNK and is power feed from injector fuse 9
B is DK GRN/WHT and is A/C compressor relay control
C is DK GRN and is A/C compressor clutch solenoid feed
D is TAN and is serial data signal.
E is BRN and is Air Pump Replay Control.
F is BRN and is power feed from FANS/SOLs Fuse 6
G is PNK and is power feed from ignition fuse 11
H is DK BLU and is secondary coolant fan relay control
J is DK and is primary fan replay control.
K is PNK and is power feed from injector fuse 10.

 

I just finished what you are starting. I used a harness from a 95 Roadmaster to start. Just strip off everything you DON'T need, used what's left over. Start at the PCM connectors and work backwards. Do one wire at a time only!! Keep everything neat and tidy while working and you'll be fine. After you're done cleaning up, lay the harness on the engine and adjust wire legnths according to the route you want. Simple. USe TONE of labels.

I used a the GM (HELM) wiring manuals and would use nothing but..get one, it's worth the money. They have all the pinouts, connector diagrams and scematics for evrything that the PCM connects to, AND all the vehicle systems in minute detail.

 

Thanks guys, It looks like a Helms manual is in my very near future !
I appreciate the info !

-Stryker-