I have a 2006 Honda Accord SE with a mystery problem. Happens every winter since we have had the car. When temperature is below freezing and snowy/damp, car feels like it is trying to downshift, slip out of gear, or misfire. Happens during straight driving, any speed. Does not trigger a code on car’s computer, so Honda has been unwilling/unable to fix the problem. They have checked the valves, electrical connections, cam, and did a software update. They don’t want to start tearing into the transmission, even though they admit that it feels like a transmission problem.
Try changing the trans fluid. Use only Honda specified fluid.
If it’s out of warranty anyway, take it to an independent mechanic and get a 2nd opinion.
How many miles? Has the fluid ever been changed?