I purchased an 88 IROCZ that the TPI was sitting in the trunk. I have since rebuilt the motor and I am now hooking everything back up. When I came to hooking up the alt it did not have a wire to hook up to the battery post on the back but it did have 3 wires (a gray(I think), white(I think), and a red) in a plug that plugs into it . Does the alt suppose to have a wire from the post on the back of the alt running to the battery or does the red wire in the plug do the job? This is a snag that is keeping me from getting it back on the road. Also does any body have a wiring diagram for this car so that I can look at so I make sure that all the wiring is where it is supposed to be.
TIA
Nathan

 

My firebird and a friends 87 IROC both have a big red wire running to the battery.

 

85 wire diagrams...
http://www.geocities.com/vtcamaro/Wire-Diagrams.html
86 wire diagrams...
http://92b4crs.tripod.com/86wiring/86wiringindex.html

Both similar (basically exact) to 88.

I was not able to find anything on the 3-wire alternators last time I borrowerd a 91 service manual from the dealership but, the wire colors to the alt. should be (but not exact) red, heavier gauge than the other 2 wire, goes to the starter. Brown, goes to the firewall bulkhead connector then to the volt gauge and tan/white stripe, should be a switched +12v source.
That may be wrong but, that's the way the harness went together in my bud's truck.

There should be a lug on the back of the alt that a 8-10ga wire from the battery terminal goes to.

 

Man! I don't think I ever want to try and put something back together that somebody else took apart.
I found the wire to the alt now all I need is to find out where all the vacuum hoses are supposed to hook up.
Anyway, Thanks to everybody that responded.
Deadbird, do you have a schematic that shows where the vacuum hose are to be hooked up?
Thanks,
Nathan

 

This is the best I have. I copied it from the label under the hood of a camaro at a dealerships back lot.