Hi guys: I just had the evaporator core replaced in my 2002 Subaru Outback sport, at a cost of $800. The day I got the car back it was making a whining and thumping noise in the AC. When I turn the AC off, the noise stops. It doesn’t do this all the time. It did it the first day, then stopped. A few days later, it did it again for a while, and then stopped. I called the mechanic who originally fixed it and he said they should look at it and that it may be the compressor. He said this would not be related to the work they already did. It seems too much of a coincidence that something else would go bad so quickly in the AC. I do not have any more money to put into this right now. What do you think? This car only has about 53,000 miles on it and I have had no other problems with it in five years.
If this noise is coming from under the dash, there is probably an electric stepper motor and door that is broken. These divert air to control flow. IF the dash came out for this repair, it is often advisable to replace these components if they are not too expensive and hard to get to. Since removing the dash is most of the cost and these things wear out, it makes sense to fix them even if they are not broken yet.