I have a 2015 Corolla CVT 1.8 with just over 138k miles. It has a strange problem that has only happened twice also both times while driving up a mountain at highway speeds. I hardly ever drive up mountains so this has only ever happened those two times I put the car through a heavy load. The first occurrence happened about 2.5 years ago maybe about 25k miles ago and it hasn’t happened since - it was also the last time I drove up such a steep grade. I never did anything about it the first time since nothing seemed wrong, I scanned for codes and nothing came up, so I just left it as is and the problem never came back. Until now (the most recent time I drove up a mountain). I was driving up a mountain on the highway going 65-70 mph and since it’s a slow car it was sitting at 3500 rpm not really gaining any speed. However after a minute or two it just threw itself into a limp mode (check engine started blinking again like it did the first time)  and I lost a lot of power. I pulled to the shoulder and turned off the car for 20 seconds. And when I turned it back on and continued driving up. The problem was gone yet again. This happened a few months ago and I also haven’t done anything to resolve the issue as my car has driven normally since then and no codes where showing up on the scanner. I am asking this because i might have to drive up a mountain next month for a road trip and I want some information on what it could even be. Maybe just a computer glitch not used to the load since I hardly drive up mountains? I don’t know. - thanks in advance for any info