You can replace the valve with a delete pipe and you won't have to worry anymore.
If you want to keep the valve, you should clean it. You'll have to take it off otherwise you won't be able to clean it well and also all the dirt on it will get into the engine.
If you want to keep the valve, you should clean it. You'll have to take it off otherwise you won't be able to clean it well and also all the dirt on it will get into the engine.