Engine power reduced

So I’ve been having this problem for a while now and it’s starting to get really annoying. I’ve had people take a look at it and even went to get the codes read and fixed everything that the codes said and I’m still having this problem. It will once in a while drive perfectly fine and then I’ll turn my car off and it’ll go into “engine power reduce mode” I still drive it on it because it’s my only vehicle. Just the other day the car completely turn off on me in the middle of a parking lot! I let it set and started it up again and it was just into his engine power reduce mode and I had to put the peddle to the ground to get any speed. I’ve replaced the battery, alternator, pedal sensor, checked the filters. Even tried to replace the mass air flow sensor but the new sensor wasn’t working proper so I cleaned my old one and put it back in. I’m so frustrated with it. Can someone help? Also, my engine light is on as well. Thanks.