It's getting pretty hot in Phoenix now, 111°F yesterday. When I start up my '94 S500s in the morining, the temp reading in the car registers ambient temp of garage around 80s and then freezes to response regardless the outside being at 90s or 100s. It will have to wait for a 5 miles local drive until the freeway or 30 minutes local drive and then the temperature reading suddenly jumps to correct reading in few seconds. At the mean time, A/C starts to pump much colder air into the vent. I wonder if this is normal or not? Both of my S500 and S500C have the same problem. Can someone kindly let me know?