Washing under the hood

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Paul2002, Jun 20, 2015.

  1. Paul2002

    Paul2002 Junior Member

    Joined:
    Nov 7, 2013
    7
    0
    0
    Location:
    Central PA
    Vehicle:
    2010 Prius
    Model:
    III
    Just bought a 2010 with 30K miles, feels huge compared to our 2002, but better handling, more MPG, quieter, and a back hatch, so I can learn to live with it.
    Previous owner doused the engine with Armour Allâ„¢ or something similar, I hate the greasy feel and the dust holding ability. Seriously, there are little pools of the stuff in the low spots..
    So what about washing the engine, any advice?
    I was thinking of a big bucket of warm soapy (Palmolive dish liquid) water with a soft broom-head type brush, a lot of gentle scrubbing followed by a garden hose sprayer rinse.
    Yes?
    No?
    Thoughts?
    Things to avoid?
    Thanks.
    Paul
     
  2. css28

    css28 Senior Member

    Joined:
    Feb 27, 2012
    1,566
    442
    3
    Location:
    Suburban Detroit
    Vehicle:
    2011 Prius
    Model:
    Three
    I'd mostly mop up the stuff with a dry paper towel and leave it at that.
     
    Mendel Leisk and Priusguy78213 like this.
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,470
    50,208
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    agreed. there are a lot of sensitive electrics in there, and some have reported problems after an engine bay wash.
     
  4. LostViet408

    LostViet408 Junior Member

    Joined:
    Jan 23, 2012
    9
    1
    0
    Location:
    California
    Vehicle:
    2011 Prius
    Model:
    Three
    Don't use dish liquid when washing your vehicle, it's a harsher chemical mix. Just use car soap.
     
  5. David Beale

    David Beale Senior Member

    Joined:
    Jul 24, 2006
    5,963
    1,985
    0
    Location:
    Edmonton Alberta
    Vehicle:
    2012 Prius
    You can use "Dawn" once in a while without problems. Under the hood is just fine (there is no real important "finish" there). Use a garden hose, not a pressure washer. "Car soap" is better, but it may not be aggressive enough. I like a "wash mit". It protects your hand and gets into tiny spaces. You may find it difficult to get all the "Armour All" off. It is very tenacious. Once clean I would apply a protective coating ("wax") of your choice, on the aluminum and painted surfaces. Tedious, but it does help to protect from corrosion.

    For those worried about the electronics, it will be fine. I washed under the hood of Pearl often with no problems and I do the same with Pearl S. As long as you stay away from pressure washers. They will force water into places it shouldn't be. ;)
    Remember, in heavy rain water gets everywhere under the hood. It's designed to resist that.

    I would -never- use "Armour All". The "wet look" it leaves is nice, but as you say, it holds dust, and in the sun tends to concentrate the energy, which can damage plastics. Especially on the dash.
     
    Priusguy78213 and frodoz737 like this.
  6. Mendel Leisk

    Mendel Leisk Witness Leader

    Joined:
    Oct 17, 2010
    57,142
    39,452
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I'd just go after the obvious "greasy kid stuff" with a damp rag. Something relatively lint-free.

    Who ever did this hopefully didn't carpet- bomb the engine bay with a spray. Or they did?....

    For regular cleaning, I'll use one of those duster wands, an old crappy one, relegated to the garage. And a paint brush, following along with wet/dry vacuum. Leaf blower works good too.

    I put foam pipe insulation year 'round on the two side lips of the engine bay, where the hood drops down without gasket. Primarily to hold heat in better, but seems to reduce dust incursion too.

    You can see them, left and right edges, in this pic:

    image.jpg
     
  7. frodoz737

    frodoz737 Top Wrench

    Joined:
    Aug 26, 2010
    4,301
    2,356
    33
    Location:
    Texas
    Vehicle:
    2015 Prius
    Model:
    Four
    ...but pull the belly pan first. I actually use Tide.
     
  8. qdllc

    qdllc Senior Member

    Joined:
    Aug 25, 2013
    1,370
    399
    0
    Vehicle:
    2013 Prius
    Model:
    Two
    If you don't want to dry out every crack and crevice, if you have a enclosed garage, just run a dehumidifier on MAX until it all gets evaporated out.
     
  9. frodoz737

    frodoz737 Top Wrench

    Joined:
    Aug 26, 2010
    4,301
    2,356
    33
    Location:
    Texas
    Vehicle:
    2015 Prius
    Model:
    Four
    A dehumidifier? It's a car...and they are designed to take water. Hood open, pan off, powered up...even in central PA (the OP) it will dry fast this time of year. If in that big a hurry just drive it dry.
     
  10. CR94

    CR94 Senior Member

    Joined:
    Dec 2, 2014
    2,642
    1,140
    0
    Location:
    Northwestern S.C.
    Vehicle:
    2011 Prius
    Model:
    Two
    i've wondered how the dealer's detail squad got the under-hood space of my car so pristine-looking before sale. At over 40K, it looked like a brand new car under there. Ever since, it's been collecting dust and stray fragments of plants and insects in every nook and cranny.
     
  11. Suprius

    Suprius Junior Member

    Joined:
    Jan 20, 2012
    23
    29
    0
    Location:
    L.A, C.A
    Vehicle:
    2012 Prius
    Model:
    Three
    For those of you that have washed your engine bay with a garden hose, did you guys spray a engine cleaner before doing it? In my previous Corolla and Supra, I did this often to keep the engine bay looking cleaning and only had to cover up and aftermarket area. However with Prius, and its inverter right up top I haven't been able to get myself to try in this car.
     
  12. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,470
    50,208
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    hair dryer?
     
  13. frodoz737

    frodoz737 Top Wrench

    Joined:
    Aug 26, 2010
    4,301
    2,356
    33
    Location:
    Texas
    Vehicle:
    2015 Prius
    Model:
    Four
    :ROFLMAO: I dare ya to u-tube that....for those that already thought the Prius was emasculating to begin with...wow.
     
    bisco likes this.
  14. gardson

    gardson Junior Member

    Joined:
    Apr 27, 2015
    18
    10
    0
    Location:
    SC
    Vehicle:
    2009 Prius
    Model:
    N/A
    I only use a sponge damp with clean water to remove the dirt and grease.
     
  15. David Beale

    David Beale Senior Member

    Joined:
    Jul 24, 2006
    5,963
    1,985
    0
    Location:
    Edmonton Alberta
    Vehicle:
    2012 Prius
    Engine cleaners are to remove oil leaked into the bay by "junk manufactured" cars. Toyota's don't leak oil. ;)

    Here's a clue regarding what "soap" might be safe. If you can immerse your hands in it for 30 min or so it's probably fine. Don't try this with laundry detergent. It can take the skin off your hands over time (from experience). Dish detergents are mostly designed to allow you to actually -hand wash- the dishes (horrors!) so are fine once in a while. In fact, if you want to "Zaino" your car and it has ordinary "wax" on it, they recommend using "Dawn" to clean off the wax.

    When I wash my car in the back yard during "not winter" time, I always wash under the hood. Don't do that in winter, as the car wash uses a pressure washer.

    It took me years to realize that even after cleaning the engine bay regularly, if I stick my hand in there it WILL come out dirty! :)
     
  16. mrbigh

    mrbigh Prius Absolutum Dominium

    Joined:
    Sep 6, 2005
    3,686
    699
    2
    Location:
    Long Island, NY
    Vehicle:
    Other Electric Vehicle
    My advice will be, get some absorbent paper towels to clean-up the Armor All accumulation over the surfaces and then diluted "Dawn" in warm water and a soft bristles paint brush; rinse with the garden hose. Do not drawn the car in water, only rinse.
    For drying under the hood I use an electric leaf blower and I use it after washing my car as well too.
     
  17. qdllc

    qdllc Senior Member

    Joined:
    Aug 25, 2013
    1,370
    399
    0
    Vehicle:
    2013 Prius
    Model:
    Two
    Meh.

    If it ever needs to be done, I'd probably do as I've always done, but I'd have to remove all the lower panels first so they don't get wet/hold in water. Spray the engine bay down with an emulsifying cleaner/degreaser (that's safe for electronics and will work at room temp since you can't get an engine "hot" in a Prius). Then hose it out with a gentle pressure spray and let air dry.

    Reattach lower panels when dry (enough).
     
  18. AzWxGuy

    AzWxGuy Weather Guy

    Joined:
    May 22, 2011
    1,010
    501
    0
    Location:
    Tucson, AZ
    Vehicle:
    2021 Prius
    Model:
    Limited
    When I bought my 2008 and my 2011 from dealers, both as the second owner, they had been "detailed", which includes gunking up the engine compartment with some sort of shiny Armor-All product. What a mess. It took me weeks of painstaking work to clean all that off. I mostly used Simple Green and paper towels and carefully disconnected pieces/parts to clean up all I could see. The lower parts of the engine and remaining compartment were subsequently cleaned by driving through a couple of signature Arizona cloud-bursts. It has stayed pretty clean since.
     
  19. Mendel Leisk

    Mendel Leisk Witness Leader

    Joined:
    Oct 17, 2010
    57,142
    39,452
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    My engine bay, pictured above, has had a bit of periodic dusting and vacuum and blow-out. Kept clear of well-meaning detailers.

    I believe the two sections of foam tubing (at the fender edges) have really helped, reduced air turbulence through there.
     
  20. SageBrush

    SageBrush Senior Member

    Joined:
    Jun 4, 2008
    11,627
    2,531
    8
    Location:
    Southwest Colorado
    Vehicle:
    2012 Prius v wagon
    Model:
    Two
    People have reported here problems after engine bay cleaning that seem to be related to water getting into the spark plug wells.

    Perhaps it is enough to just avoid using a water jet under pressure, but I have no comforting experience to relate.