I have an 89 with 40,000 miles that has an AC problem. I'm hoping someone here can offer a solution. I rarely drive it more than 15 to 20 miles and the problem happens on longer trips. The first time it happened was about 4 years ago. The alert showed that I had low refrigerant level. I went to the dealer here and ended up converting from R-12. A year ago I had the same alert on a 100 mile trip. I took it to dealer and was advised that refrigerant was just slightly low. They evacuated and filled the system, but could not find a leak. Well, last week was the first long trip since and I got the same alert. Strange thing is, when the alert comes on the air blows warm. After getting home driving around town AC works fine and no alert. It seems to me that this has to be a problem with a sensor or some other electronic device as opposed to refrigerant actually being low. I talked to the owner of the dealership and he said that with the problem being intermittent it would be hard to diagnose. He said if I could give him an idea of what is causing this, he would take care of it. So, I'm hoping that one of you folks might have had this problem and has an idea of how to solve it. Thanks, John