I drive a 1999 Toyota Corolla with just over 138 thousand miles. It is a manual transmission. The transmission itself was replaced ~4 years ago, so it is not 12+ years old.
As the weather has turned colder and wetter I have noticed that during rain my car has trouble shifting properly. When I start it up it starts fine, but once I start driving it will seem like the clutch is having trouble catching. Often the car will run as if I had the clutch pressed almost completely in, though based upon the low pitched sound of the engine (I don’t have a tach… even though it’s a manual) I know that I’m not revving the engine really high as if the car was in neutral. The car will sort of coast along at about 10% power for a few seconds, give a couple lurches, the engine will suddenly catch and rev higher and I will speed up to match the new higher rpm. Once the engine has caught I don’t have a problem until I need to shift up, when the whole issue repeats itself. This doesn’t seem to happen in 4th or 5th gear, and by the time I reach my destination it has usually stopped happening completely.
Today the same problem happened, but it was so bad that I stalled multiple times while trying to start from a stop. When I stalled the first time, it was quite difficult to get the car to start again. Fortunately I was only at the entrance to my apartment complex so I was able to limp back to the parking lot. Oddly, going in reverse did not seem to pose as much of a problem in terms of shifting.
Again, this problem only seems to happen while it is raining out, or after it’s been raining recently. If I rambled a bit it is because I am trying to include every detail I could remember about the times that this has happened. Does anyone have any ideas?