OK, Let's try to explain.
I have a Corolla 2009S 138000KM, 3 times this year I fill in the car with regular gas, then when I accelerate the car will accelerate very slowly I would say at 0-15 everything is normal it's after this, I put some Injector cleaner and I fill in with Supreme instead of regular and the problem went away. Now friday, I fill in the tank with regular and it took some time but 20 mins after same thing happen, I had to press harder than usually to get speed. (Again after 20 KM), I added injector cleaner and still doing it, then the check engline light...
The check engine light was on & off and it finally stayed so I went to my garage, the code said something about the knock sensor. They follow the procedure and they replace it after troubleshooting, when I got home, I tested the car, still the same thing about the performance. I also played with the automatic shifter and If I change it from OD to 3rd, the RPM will works fine for 2-3 times, then the light will come up (Check engline with the same knock sensor and this part has been replaced).
Don't know what to think now, they charged me already 600$ (They changed the oil in the transmission too) and it's still doing it... Level was fine and nothing that tell it's a transmission problem. They cleaned up the MAF sensor, they look at the filter in the gas tank (Under the seat) and also look for water in the tank... The next thing wil be injector cleaner but ...
Sorry if the terms are not right, i'm french trying to write in english