Problems with coolant sensor

I just need to know where the Coolant/Antifreeze Sensor is located on a 89' Buick Regal Custom V6 - 2.8L - fuel injection.

If anyone knows,

if not, can anyone help me with a/c?

I have a/c but, it is blowing very little cold air, no matter if it is on high or medium.

if you have any suggestions about either or both, that would be very appreciated.

It may be on the firewall side of the lower intake manifold, near the throttle body.

Thanks