So I did something, that I felt was, incredibly stupid today. I am in my third trimester of pregnancy and sometimes get incredibly foggy-brained. Anyways, I live down a somewhat steep hill, heading down a mountainside, and I usually shift my automatic transmission into first gear to try and save some wear on my brakes heading down. Well today I completely spaced out, and before I realized what I was doing I had shifted into park, still rolling down the hill. I don’t exactly remember what the car did except for that all of my dash lights came on, I had maybe rolled 20 or 30 feet. I managed to shift back into drive very quickly but my car just felt strange. I tried to brake because I was gaining speed, but, low and behold, nothing happened…my foot was to the floor and my car was still rolling, maybe slowed slightly, but I had to pull the E-brake and stop the car. Stopped, I put the car back into park, shut it off, and restarted. At this point I didn’t notice anything wrong but I was a bit shaken up from the incident. Could I have possibly damaged something? I’m not sure if I should be worried. I haven’t been eager to try and go anywhere considering it’s all downhill from here.
There is normally no way what you did would damage the brakes. Possibly you lost brake booster vacuum momentarily. I believe yours is a CVT automatic transmission. I would have the transmission fluid changed as a precaution (special CVT fluid, at a dealership). I’m assuming the car now runs normally in every way and PARK holds the car stationary on a hill. There’s a good chance you have done no permanent damage. You can always have it towed and checked if something doesn’t seem right.
I’m guessing the engine stalled and as Insightful said you lost your power brakes. Did the car drive and brake normally after it was restarted? I remember my wife managed to lock herself out of her car with the engine running when she was near her due date with our first.
I think it is fairly obvious that the OP’s engine stalled, thus leading to a lack of power assist for the brakes. As to possible transmission damage, I suggest that the OP follow insightful’s advice and have the trans fluid changed a.s.a.p., just in case a shard of metal was sheared from the park pawl when the trans was shifted to “park”.
"heading down a mountainside I usually shift my automatic transmission into first gear to try and save some wear on my brakes heading down."
Good point. It’s always easier to drop the transmission and replace worn transmission parts than to replace brake pads.
The parking paw is moved into place through a spring-loaded mechanism and won’t engage the park gear if the car’s velocity exceeds a government-specified park lock engagement speed somewhere between about 0.7 and 1.5 mph. At higher speeds the paw should just overide the rotating gear on the output shaft and not engage.
For your safety in the future, you need to be aware that you can stop the car without power brakes, but you need to use a lot of force. In your case, it sounds like you might need to use two feet. Keep that in mind if your car ever stalls again.