I was at the shop today purchasing some PB blaster and I noticed an ENGINE FLUSH fluid on the shelf. Since I am changing my oil this weekend I thought I might do the engine flush as well but I wondered if it would harm the engine. The directions on the bottle say to pour all of the contents into the engine (where the oil is poured into) and to let the car run for 5 minutes, after that it prompts you to continue with the normal oil change. Does anyone suggest I flush my engine? oh and I have a 2004 3.9L V6. Thanks