There are many causes like detonation, or spark knock trigger a terrible engine problem and that problem of the car engine can be serious. Due to the detonation, or spark knock, the car engine may get too much temperature and compression in the engine’s combustion chamber. So, you must take the car to an automobile engineer to solve the car engine problem. The engine P1845 Code also helps to fix the car engine and solve the problem by a correct way. The general meaning of the code is helpful but it is not correct thing for solving the car engine problem properly.