I've found my problem with the two solar panels, and likely most owners problems. The solar panels are not aimed like they should be. They need to be angled toward the middle more. When the sun gets into the center of the sensor, (due south) that is when the motor slows down, and in some cases stops completely, and then it doesn't start up again for a while, or get back to full speed causing the daytime temp to be 5* F or even 8* F on some days high. What we need is a solar panel in the center or to angle the two on there more into the center. If anyone knows a good way to do this, I am betting this will take care of a lot of problems. My sensor does great and keeps within 1* F of my new acurite tower sensor in a large inverted bowl shield until the hours of 11 AM to 3 PM. Many think the motors are failing, but I am doubting most actually are bad. If there isn't enough power to run it full speed, it will be slow.