Qon.i start is very uninformative. Will the engine crank or does nothing happen when you turn the key? If it won;t crank do you hear a click when you turn the key? If it cranks, do you hear the fuel pump run if you just turn the key to “on” without cranking the engine? Do you smell gas if it cranks but won’t start? Does it ever “sputter” when cranking like it is trying to start?
These are all things that will tell your mechanic what system to look at. Just telling someone that it won’t start and then having it start when it gets to them doesn’t give them a clue
If you let it sit for hours will it start in your garage