Wash the Engine
You and I both know, if you merely open the hood, and put your hands in the area of the engine, both your arms, up to your elbows will turn pure 100% black, instantly. :)
I love washing the engine.
Before you do just about anything in the engine, this is a HIGHLY recommended item.
Go down to the car wash place, and pop open your hood. If you have an After Market Intake Installation cover it up with a bag, but then go to town and soap it up with high pressure soap option, then rinse it out with high pressure rinse. Get down on your knees and spray underneath.
Best $2 you can ever spend.