PronessDave

I should have mentioned that I am using this on my 2002 Subaru Impreza WRX on a EJ205 motor

I was planning to use the upper engine cleaner after my service because i lost the small tube thing and have to go get it from somewhere but I heard people saying that it is better to use it before the service so all the dirt and grime can be removed with the oil. Can I still use it after the service or should I just wait till my next service to use upper engine cleaner?