no, that's not it, I know what he's talking about...
There's a product available at most auto parts stores, it's an engine bay cleaning product made by Gumout called Steam (it's in a green or grey aerosol can)
This stuff doeas an awesome job. it's easy to use too.
Buy a can of Steam, or a similar engine degreasing product.
Run the car until it heats up to full operating temerature, park the car in your driveway, or wherever you will clean it.
shut off the engine, and wrap the Intake
filter in plastic of some sort, or put a plastic bag over it with a rubber band securing it.
Now, with the engine still hot, spray the contents of the can all over the engine bay, on the engine, firewall, inner fenders, everything... until the can is empty if it's real dirty, a can is good for 1 or 2 cleanings.
let it sit for about a minute or two, after which, you hose down the engine bay. use a towel to soak up any water puddles on the valve cover, or in the nooks and crannys of the engine bay.
Avoid spraying electronics and alternator, but some water won't hurt (unless the ECU box is leaking of course!)
Viola! your engine bay is spotless!
Remove the plastic over your Intake
and you're done!
Spme people prefer to remove the engine plastics first, and clean them seperately; this is considered the preferred method, and the one that I use myself.
This is what most people mean when they talk about steam cleaning an engine. using an actual steam cleaner will take a lot longer than this method.
Below is a pic of a can of Steam.