My daily driver, a 99 Camry, has developed a peculiar automatic transmission problem. It won't shift to a neutral while coasting in drive. If I am gently accelerating say in 3rd or 4th gear and then let completely off the gas, it will stay in that gear and the rpms will not fall. What would cause it to do this? Occasionally it has held onto third at about 2500 rpms. Even though my foot is not on the gas, it will maintain speed decelerate very slightly. Normally it would shift into neutral. The transmission works just as it should the rest of the time, with no roughness in shifting.
Could this be a cruise control issue? I have tried numerous times to turn it on and off and to see if the accel/decel has any effect, but it has none. Any ideas?

 

try it without the cruise control fuse, so theres no chance of the cruise control effecting anything.

 

markland that is a great idea