Okay, I checked the forums and couldn't find an answer to this problem I 've been having. I have a 98 Lexus GS 300 with 147,000 miles. My air conditioning blows ice cold at 65 F. My problem is that's all it will blow at. When I change it to 70 F it blows cool air then after about 5 minutes it blows hot air, really hot air. When I change the temp back to 65 it blows cold air again. Does anybody know if there's some sort of sensor that went haywire somewhere? The AC module in the cabin runs about $400-500 bucks. I was going to swap this out but I don't know if it will help. The guys at Lexus seem baffled. They tell me to swap out the unit but they also tell me that they are not sure if it will work. I hope I'm not the only one with this problem.

 

I just got my ls430 back from service and some kind of "blower door" (?) part was stuck, only got hot air out, they fixed it right away.

 

Thanks for the input. I wish it was just a blower door that was stuck. See, it works sometimes where I put it at 70F but then a few minutes later it blows HOT air. I turn it down to 65F and it blows cold air. From the lack of responses, it looks like I'm the only one with the problem.