1991 Honda Accord The S for the sport is blinking

My 1991 honda accord has a automatic transmission. On the shifter is a button labeled sport or normal. When the sport is engaged the s on my instrument panel lights up. As of recently the car at times will turn over but not want to fire up. When it finally does the s for the sport will blink and transmission acts like its barely in gear. What causes this. I know its blinking for a reason.I would like to think I have some sort of sense but this has me stumped. Checked all fluids any visible damage or significant leaks. And everything checks out. If anyone has any idea what this could be please share. Your time is greatly appreciated. Thank you all.