Hi folks. There are a lot of write-ups about cleaning engine bays, but few that focus on a very, very greasy engine that has never been cleaned and that would really not be safe or kind to do on your driveway or street.

This may look like a lot of steps, but it's very fast. I've just tried to detail every step I took, however small.

Very Greasy engine wash on the cheap without staining your driveway
• Applies to Toyota 4Runner 3.4L V6 engine (3rd gen 4Runner and others)
• Maybe $20 of car-wash time cheap compared to $150-$250 for someone else to do it.
• Avoids dropping chemicals and oil onto your property or into your storm drains
• Local self-car-washes typically collect and recycle the water and oil - much better for your children's planet and local laws.
• 15 minutes prep, 30 minutes at the carwash. Probably faster than driving to and from a pro detailer.
• High pressure is often needed on really greasy engines, but people shy away from it because it's tough on sensitive parts. Take these steps and that won't be an issue.

What's needed:
• Full spray bottle of Simple Green or you fave degreaser that doesn't etch aluminum
• Spray bottle of water (optional)
• 303 Auto or Aerospace protectant spray (satin and doesn't attract dirt) or similar
• Large, old baking tray or something to protect the trunk of your car
• Regular size old baking tray
• Kneeling pad, piece of old foam, folded towel so you can kneel or lie on the ground.
• Disposable gloves
• 24" ish flexible grabber / retriever / claw tool ($7)
• Ideally coveralls or old clothes that you can remove once they're wet (and have dry clothes underneath).
• Battery powered leaf blower (optional)
• Roll of tin foil
• Roll of kitchen cling wrap
• Roll of blue tape
• Roll of duct tape
• Plenty of rags
• Kitchen trash bag cut in half to cover battery and fuse box, then alternator (optional)
• Roll of paper towel
• Dry slip-on shoes
• Safety glasses / goggles

Quick prep at home with cold engine
• Lots of oil and dirt accumulates in the Vs of the engine where the valve covers leak over the years
• Cover electrical plugs in those areas with blue tape (since this is low to no pressure)
• Spray Simple Green into those valleys
• Cut up a strong rag like a t-shirt into 4"x4" squares
• Grab the center of the rag with the claw of the grabber and push and pull the rag back and forth along the valleys while spinning to liquefy and soak up all the oil & simple green.
• Throw out and use new squares often. Keep flooding and repeating until most thick stuff is liquefied and soaked up.
• Do a final quick rinse and soak up of the area with water from a spray bottle and the rags so Simple Green doesn't sit on a hot engine when you start up
• Put all your supplies in the trunk. Liquid things on the small baking tray, which sits in/on the large baking tray.

At the self-car-wash
• If possible, keep engine cool while driving to a close-by self-car-wash
• Park in the car wash bay, leave the trunk open
• Allow engine to cool if needed and disconnect both sides of the battery and wrap connectors with cling wrap or duct tape.
• Cover battery and connectors, and fuse box in plastic bag and tape down, or the pressure washer draft will just blow it off.
• Cover alternator as above (or avoid spraying it if you're daring)
• All small electrical and data connections, cover with aluminum foil, since it molds nicely. MAKE SURE battery is disconnected - foil is conductive
• Wrap duct tape over aluminum foil if needed for extra protection. Doesn't have to be 100% water tight, you're just trying to avoid getting high pressure water in these plugs etc.
• Cover stickers under hood with blue tape
• Reach over to back of engine and run a long band of blue tape along the top edge of the firewall insulation pad, sealing the top edge and taping it to the firewall. Tape over the blue tape with duct tape to the firewall as this withstands water pressure better than blue tape alone. Don't just use duct tape on the insulation pad, as it will stick to, and rip the pad. Blue tape first, then duct tape over top!
• Cover top of oil and transmission dipstick tubes and handles with foil (and tape over if needed)
• The ground is gross and wet. Put small baking tray (with the kneel pad / towel inside it) down on wet ground beside the truck. It's raised edge will keep your knees or hip dry.
• Wear safety googles!
• Kneeling on the tray (or laying your hip in it), spray Simple Green on underside of engine and transmission. If really greasy, let it sit awhile.
• Using high pressure, spray underside of trans and engine wherever you sprayed the Simple Green.
• Use flashlight to see what you're doing. Spray until all grease is gone. Down here it's OK to have the high pressure close, other than near openings.
• When that looks good, set the small baking tray back onto the larger tray in the trunk and move to top of engine.
• Spray simple green down low inside engine bay, especially below the pulleys around the top of the flange where the block mates to the oil pan. Also the chassis rails and inside the top of the skid plates.
• High-pressure wash lowest parts first, so water and oil from above doesn't obscure what you've done.
• Work your way up on the engine and inside engine bay, spraying Simple Green, including soaking inside the V valleys on top of the motor. Make sure you're still wearing goggles, spray into the V valleys at top of engine that you prepped earlier. Much water will spray back at you! The US driver's side valley is mostly obscured by the intake manifold. Do your best. Nobody will know!
• Keep going until whole engine is washed.
• You can switch to Simple Green and low pressure wash for sensitive stuff like throttle linkages, or joins between pipe, intakes etc.
• Spray firewall, avoiding grommets and if possible, avoid the duct taped edge of the insulation pad, or make the spray as perpendicular to the duct tape as possible, so you don't lift it up.
• Wash underside of hood, avoiding stickers you've taped up, do those manually later
• Avoid the things you've taped up, those are most sensitive and you clean those manually later
• Finish with low pressure water from top to bottom.
• Give the fenders and front bumper and grill a bit of a low pressure rinse
• Use leaf blower and dry off engine, starting at the top. Don't force water into stuff
• Use towels / rags to dry off as much as possible, don't worry too much about the stuff closest to the ground
• Uncover and start to let battery dry - don't connect yet.
• Start removing all pieces of foil and tape. Dry those connectors with rags and leaf blower. Don't forget to gently remove the tape from the firewall pad.
• Once all foil and tape is removed, dry and clean battery terminal connectors and reconnect.
• Pack up - put the smaller wet baking tray and your wet clothes onto the large tray in your trunk. This will keep your carpet dry.
• Take off your boots and slip into the dry shoes.
• Fire up! You've been careful, it will fire up with no problem.

Once home
• Once truck is cool, manually clean some of the parts that you taped over, with some paper towel soaked in some simple green, finished by paper towel soaked in water to remove the Simple Green.
• Lightly cover the 3 v-belts at the front of the engine with an old t-shirt or towel (so they don't slip and squeal later).
• Use 303 aerospace or 303 automotive protectant spray and mist the whole motor, with some more focus on the plastic, rubber and black-painted parts. Wipe off excess and lightly buff
• Don't forget to remove the towel covering your v-belts, that would be embarrassing
• Admire your work

Wow that IS very detailed. I would add that you can have a clean, dry engine by replacing the VC gaskets. Once you stem the flow the engine will clean itself via burn-off. I like to live dangerously and spray the engine directly with their 'engine cleaner' mix and then blast the engine bay with the Turbo Dry gun. Usually just for mud and dirt. My motor is clean as a whistle and dry since I did the VCGs that pretty much every 3rd Gen needs. But, I'll admit my shoes do get a bit wet.