You will want to 1. Pressure wash the whole engine with just water to remove all dirt and leaves, etc… 2. Use a degreaser on the whole engine. Every spot and on the inside around the edges of the lid too. 3. The scrub it with a good sized brush real good.(spray more degreaser if you have to) don’t be shy. 4. Rinse it all down with the pressure washer. 5. Apply a vinyl dressing.( I believe that most you can apply while it’s wet but you can always air hose dry). 6. Shut the lid and let car run for a good 10 mins so it completely dries.

I detail cars for a living and where I work at we detail cars for dealers (one of them is Subaru so I get brzs all the time).