Auto Air Conditioning & Heater Repair: can coolant leak into the a/c?, coolant water, coolant level

Question
Dear expert,
I have a 2001 Toyota Sienna with 200,000 miles. After driving to the mall, I noticed green coolant on the some place beneath the car where usually the water drippings from the a/c are, when we returned from shopping. There are absolutely no coolant / water drippings on our garage floor, but the coolant level in the expansion tank went down a little bit since last the time I checked it.
There is now smell inside the Sienna, but since a few days the a/c makes a soft hissing noise each time it comes on.
What do you think? Can coolant leak into the a/c? What can cause the problem? I hate going to Toyota Service because each time I went to them I came out with a $1500 to $2200 invoice.
Thank you very much,
Peter


Answer
Hi Peter

Check coolant level and see if it comes down.  If level is OK then check your ac pressure.  From the hissing noise you have it could be that your evap. is leaking refrigerant and you may have dye in the system. Let me now what you find if it is coolant your heater core is located at the evaporator case and will drain out of the same drain port.