1996 Chevrolet S 10 Recently Went Offroad S10 Stalled Puddle Engine Hydrolocked

I recently went offroad with my s10 and stalled in a puddle. my engine was hydrolocked so we did an oil change and spark plug change. after that it ran fine the entire next day, but in the morning when i went to start it, it will turn over and idle for a second then stall unless im constantly pressing the gas pedal. A code shows up reading mass flow air sensor circut/ low frequency detected. I then purchased a new mass flow air sensor and installed it, but there is no change. Any ideas on what the problem could be?