Is Engine Cleaning a scam maintenance Job? Flushing vs. Cleaning?

The guys who do my oil change wrote a note recommending their "three-part engine cleaning" a little googling around has shown that if they mean an engine flush- that that is an unnecessary and possibly damaging procedure to do to your car. Could they be talking about cleaning the outside of the engine? Would there be any legitimate reason (other than cosmetic) to do that? Or does it sound like they are trying a scam?
Is Engine Cleaning a scam maintenance Job? Flushing vs. Cleaning?
If they are talking about engine coolant flush and drain, this is a recommended maintenance item on most auto mfgs. Go to your owners manual and see what intervals they recommend. Done properly this will extend the life of your engine, radiator, hoses etc. As it removes contaminants. If they are talking of exterior of engine if not done properly you could have some major problems with you firing system etc. due to too much force with steam cleaner etc.
Reply:Its not a cosmetic thing they don't clean the out side of your enigne they clean the inside parts LOL. If they clean the fuel injectors than that's is fine I clean mine once a year. they sell this stuff called sea foam its amazing I have a 15 year old car with 175,000 miles with a V6 that still gets 20 MPG with mostly driving around town. But if they want to flush the oil pain out than yes this will mess up your engine especially if it has high mileage. What happens is that the engine flush will dislodge allot of the sludge that has build up on the bottom of your oil pain over the years and it will send it to the oil pump and clog it up which will starve the engine of oil and damage it which will cost you thousands to have fixed. if you want a clean engine than switch to synthetic oil it has the ability to clean the engine much better than regular oil and you will also see an improvement in gas mileage.