A simple garden hose is fine for spraying it off. Do not use oven cleaner, because it is caustic and corrodes aluminum real quick.
Do cover the altenator, because water can kill the diodes if it enters through the micro cracks in their cases as happens over time.
The dirt the engine gathers is usually water soluble and therefore no detergent needed, because nothing on this engine leaks oil.
Ummm...has anyone actually had an oil leak on one of these cars? If you are just spraying off dust and/or dirt, water will do just fine.
No grease = no need for degreaser.
I would cover up the end of the air intake tube.
Bleach? Oven cleaner? Sweet ****...
Any rubber safe degreaser. Wet, apply, wait, rinse. Reapply, wipe, rinse.
Dirt and dust wont rinse off, you do need a solvent to get your plastics black.
View my fuel log 2018 Mirage ES 1.2 manual: 43.1 mpg (US) ... 18.3 km/L ... 5.5 L/100 km ... 51.7 mpg (Imp)