Chevrolet: coolant leak?, chevy caviler, bars stop leak

Question
I have a 99 chevy caviler. I am loseing coolant but I can not find any leaks. I took it to my locale chevy dealer and had them run a pressure check on it and everything came up good. So I bought a new cap and put it on. Didn't seem to help. I don't see water in the oil and I don't smell or see white smoke out of exhaust. Plus it dosen't run hot. The hottest I have seen it get is about 225 and I stopped in traffic alot on a day when the temps were in the 100's. The only place I can see any sort of water is on the air conditioner pump. And it is on the bottom of the pump. The can't see any water coming out of the weep holes on the water pump either. I did have to have the head replaced while on a vacation in New Mexico. I live in Montana. And I didn't have any problems with anything on the way back. Actually the car almost never runs hot enough to even open the termostat. Usally it runs about 175. I did buy a new water pump to try that, but haven't put it on yet. I was hoping you might be able to shed a little light on the subject. I can only go about 100 miles before I get the low water light. Thanks, Dave

Answer
Dave ,
    I would get a can of BARS STOP Leak  and put that in the rad. it will seal up any pin hole that you might have , when the light comes on is the water/coolent low ? or is the light  just comming on? I would add the stop leak and see what happens , it can no hurt at all..  ok