When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The best way is go to anyparts stores and buy engine degrease remover. Go to your local car wash. Go to the one you know that has the best pressure. Spend a good $5 or so worth of quarters to wash it. Make sure you dont wet your air cleaner. If you have to put a bag over it. Most manufatures make the engine bay water resestent. So becarefull where you spray. Or just use your house hose but not the best pressure!
I always use "Greased Lightning" degreaser spray. You can buy it cheaply at Wal-Mart, Lowes, or dollar store. Just spray it on, wait a few minutes for it to break down the dirt and grime, and just rinse off. It works great on tires, too.