Sorry I can't upload a picture right now for some reason. The pulley is directly underneath the A/C compressor. I followed a wire directly from the battery to it. To me this seems like the starter,but I've never heard of a starter being driven by the serpentine belt. It's 1991 Camaro RS 305 TBI by the way. Sorry for the newbie question.

 

Your comment about a wire from the battery going directly to it leaves me clueless.
Otherwise, I would be 100% confident it is the smog pump.

 

wire had me puzzled too ,but I kinda recall on my '82,when it was still dead stock,battery negative cable was grounded to smog pump bracket...

 

x2 8t2 z... The lower pulley is the AIR pump for emission controls. That is the NEGATIVE battery cable for the engine ground.
You'll find the starter under the passenger side exhaust, at the back/middle of the engine, along with the POSITIVE battery cable.

 

This was a positive wire from the battery. It's a small wire from the battery;then it goes forward into some sort of junction or something (no clue) then it splits off into its own wire again and leads to back of the pulley.

 

It sounds as if your describing the alternator ? If your 100% sure a wire runs from it to the battery + , then it's gotta be the alternator your describing cause no other device that's serpentine belt driven has a direct wire to the + side of the battery ....

 

It's not the alternator haha.

I found a pic online I can use.

 

That's where the A.I.R. pump is located. But that picture looks like a bypass pulley because of the cheapo plastic pulley. Either way, neither will have an electrical connector.

 

What's the A.I.R. pump for?

 

Hi '91 . The AIR pump is part of the emissions system. It pumps outside air into the exhaust manifolds and/or the catalytic convertor. It is required to pass inspection in some areas. It can be eliminated from the car.

al

 

It certainly isn't , now that you got a picture . It is , as eseibel67 says , a delete pulley for the air pump .

Oh , and ,

I can ASSURE you there is no wire electrically connected between that pulley and the positive side of the battery !