Step-by-Step Guide to Engine Detailing
ABSOLUTLEY REMEBER THIS TIP!!!!!
Do not wash the engine unless it is cool.
Cover/wrap any electrical component that might get wet while washing with a plastic bag (grocery bag) or saran wrap. Parts to cover include the distributor, alternator, fuse box (optional) and any exposed wiring connectors.
In my opinion, a pressure washer is not needed and will only cause you grief. Using the garden hose, rinse the engine bay using low pressure. Just give a quick rinse of the engine bay, not blasting it, and keeping away from the areas of concern you previously covered. Go over each area of the engine and do not let the water run over the same spot for an extended amount of time. The goal is to just wet the area, and rinse any lose debris off.
Use a good all-purpose cleaner such as Duragloss APC or Meguiar's APC. Simple Green can be used, but it has been reported to etch aluminum....I haven’t seen this happen myself, but others have reported it so be careful.
Spray your favorite APC throughout the engine bay. Let the APC dwell for a few minutes and it will start to break down the oil & grease on its own. Next, grab some various brushes and sponges, (detail brushes, Daytona wheel brushes, tooth brushes etc.) and give the engine a good scrub. Easily accessible areas can be cleaned with the sponge (underside of the hood, valve cover, exposed paint, etc.) The harder to reach and dirtier areas are what the brush is for. It's fine to spray on a little more APC on areas that you need to while scrubbing.
After you have finished scrubbing and the engine is degreased, rinse the engine bay, using low pressure and let the water run over the engine. You can do more scrubbing with the brushes, and even add a bit more APC to areas that you've missed or need a bit more work. Rinse thoroughly.
Do not air dry the engine. Using some old MF towels, hand dry each part of the engine bay you can reach. Also some compressed air works good here. Just be mindful not blow the water into unwanted electrical areas. Unwrap the electrical components and use one of the more damp towels to wipe them down. Then dry them with another dry towel.
Plastic & Hose Detail
To dress and protect the engine and hoses and other under-the-hood plastic, look to use Sonus Trim and Motor Kote, or another top quality product such as Meguiar's vinyl & rubber dressing or 303 aerospace protectant. I personally like the Sonus Trim and Motor Kote because it has never attracted any dust or dirt.
If working with any product except the Sonus product, spray the dressing directly onto the towel and then wipe down the hoses and other plastic. The Sonus product works a bit differently. Let the dressing dry before driving, and I suggest leaving the hood open in the driveway in the sun for a couple of hours to ensure it is dry.
And that should do it. You will have a perfectly detailed engine bay worthy of any car show!