1. PriusKyle

    PriusKyle New Member

    Joined:
    Mar 12, 2022
    17
    8
    0
    Location:
    Virginia
    Vehicle:
    2011 Prius
    Model:
    Three
    Hey all,

    At the 120,000 maintenance mark, among other things, spark plugs are to be replaced but it has an asterisk next to it.

    “Maintenance services of spark plugs are required under the terms of the Emission Control Warranty. For vehicles
    corresponding to PZEV for California, Maine, Massachusetts, New York and Vermont, replacement interval is
    150,000 miles.”

    Outside of those states cited (change at 150,000 got NY, Ca etc.), it sounds like spark plugs aren’t really necessary to change at 120,000 except for warranty requirements.
    On a purely technical maintenance reason, is it really necessary to swap out my sparks at 120,000 or can I get away with it and wait til 150,000 without harming my vehicle?

    Thanks!
     
  2. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    15,835
    8,082
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    If you already have the windshield cowl removed for maintenance, you should just go and do the plugs at the same time. Once done, it'll be good for another 120k miles. For most people it's a 1 time event, as they normally won't keep the car long enough to do it again after 120-150k miles
     
    PriusKyle likes this.
  3. Mendel Leisk

    Mendel Leisk Underfoot

    Joined:
    Oct 17, 2010
    49,133
    35,037
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Sounds like miles and months are close to sync'd anyway, but fwiw, the regular spec for plugs change is 120K miles or 12 years, whichever comes first.

    If DIY'ing get the plugs from a reliable automotive retailer or dealership, avoid EBay; there are lots of counterfeits.

    Note: the orignally spec'd Denso SC20HR11 has been supersceded with Denso SC16HR11 now, slightly hotter.

    Good video by @NutzAboutBolts, on how to get to the plugs:



    In the video they slather anti-seize on the plug threads, then torque to 20 foot pounds. Repair Manual (excerpt attached) says 15 foot pounds, and no mention of anti-seize, so presumably clean/dry threads. If you do use anti-seize, keep it light and reduce torque to 12~13?
     

    Attached Files:

    #3 Mendel Leisk, Mar 17, 2022
    Last edited: Mar 17, 2022
    w84me and NewShockerGuy like this.
  4. PriusKyle

    PriusKyle New Member

    Joined:
    Mar 12, 2022
    17
    8
    0
    Location:
    Virginia
    Vehicle:
    2011 Prius
    Model:
    Three
    Thanks to all that replied; I’ve already scheduled it to have it replaced since it’s something I won’t have it done again Amin a while, might as well it earlier than later.
     
    bisco likes this.
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    100,032
    45,334
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    and clean the egr circuit, pronto
     
    Mendel Leisk likes this.
  6. Michael Wood

    Michael Wood Active Member

    Joined:
    Jun 19, 2016
    160
    105
    3
    Location:
    Boston, MA
    Vehicle:
    2020 Prius Prime
    Model:
    LE
    I removed these today from my 2015 Gen 3 Prius with 162k Boston miles. These are the original plugs. They probably could have made 200k.

    And off course I found the obligatory rodent's nest I thought I had neatly side-stepped. Luckily I didn't see any damage.
     

    Attached Files:

    CR94 likes this.
  7. CR94

    CR94 Senior Member

    Joined:
    Dec 2, 2014
    2,132
    886
    0
    Location:
    Northwestern S.C.
    Vehicle:
    2011 Prius
    Model:
    Two
    Good to know they can easily go that far. Just for curiosity, how wide have the gaps grown at that mileage?
     
    Michael Wood likes this.
  8. douglasjre

    douglasjre Senior Member

    Joined:
    Sep 13, 2008
    1,194
    439
    0
    Location:
    Orlando, FL
    Vehicle:
    2010 Prius
    Model:
    ----USA----
    We are finding the spark plugs are not reliable beyond 120,000 mi. I would even suggest to replacing them at 100k to have a round number that's easy to remember and reduces your chances of putting access strain on your coil packs which are vulnerable to premature failure anyway
     
    Michael Wood and Grit like this.
  9. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    5,591
    3,846
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    How they look, they’ll make it to 200k with misfires along the way.
     
  10. Mendel Leisk

    Mendel Leisk Underfoot

    Joined:
    Oct 17, 2010
    49,133
    35,037
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I’m coming up on 12 years, the CDN spark plug change interval, AND at 95k kms. The kms criteria is 192k km IIRC (120k miles), and I’ve already resolved: I’m leaving them be till year 15, the next coolant change interval. Will do the coolant, take off the wipers to do plugs, and revisit EGR/intake cleaning.

    I did pull the plugs once previous, around 50k kms, just for a look.
     
    Michael Wood likes this.
  11. Michael Wood

    Michael Wood Active Member

    Joined:
    Jun 19, 2016
    160
    105
    3
    Location:
    Boston, MA
    Vehicle:
    2020 Prius Prime
    Model:
    LE
    I bought my replacement plugs at the dealer because of all the fakes around. The new plugs are Denso SC16HR11 and the originals are SC20HR11. I eyeballed them and the gaps looked identical - but I didn't measure them.

    BTW - the originals came out really easy.
     
    douglasjre and CR94 like this.
  12. douglasjre

    douglasjre Senior Member

    Joined:
    Sep 13, 2008
    1,194
    439
    0
    Location:
    Orlando, FL
    Vehicle:
    2010 Prius
    Model:
    ----USA----
    Any idea why they went to a hotter plug?
     
  13. douglasjre

    douglasjre Senior Member

    Joined:
    Sep 13, 2008
    1,194
    439
    0
    Location:
    Orlando, FL
    Vehicle:
    2010 Prius
    Model:
    ----USA----
    Michael: on the official site I'm seeing heat range 20 is still spec. Where did you get your information?

    BPR6ES was used on some Kawi and Nissan engines in the 80s and 90s. We had a problem with 6es failing and the fix was to use 5es plugs. Can't imagine going 4 heat ranges of change.....


    Spark Plugs. 2010 Toyota Prius Base | Toyota
     
  14. Michael Wood

    Michael Wood Active Member

    Joined:
    Jun 19, 2016
    160
    105
    3
    Location:
    Boston, MA
    Vehicle:
    2020 Prius Prime
    Model:
    LE
    Mendel Leisk likes this.
  15. Mendel Leisk

    Mendel Leisk Underfoot

    Joined:
    Oct 17, 2010
    49,133
    35,037
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Just ask dealership parts department; they get these updates. And doing it over the phone, you “can” hang up and buy elsewhere, if their prices are prohibitive. OTOH, if it’s a buck or two more per plug, and with counterfeits circulating…

    interesting, in the link they even advise spark plug retailers to sell off their “20” stock, before moving to “16”. In other words, it’s NOT that critical.

    our 2010’s still got the “20” plugs, they looked fine when I had a look at them (around 60k kms IIRC). Technically “due” this November, the 12 year mark, but I’m stalling to 15 year mark, when coolant changes are due again. My justification for delay: only at 95k kms currently.

    will revisit EGR at that time too.

    Unless I fall in love with 5th gen. Suspect I won’t. Or will be able to restrain myself. Maybe…
     
    #15 Mendel Leisk, Oct 4, 2022
    Last edited: Oct 4, 2022
    Michael Wood likes this.
  16. NewShockerGuy

    NewShockerGuy New Member

    Joined:
    Sep 28, 2022
    16
    11
    0
    Location:
    NOVA/DC
    Vehicle:
    2016 Prius
    Model:
    N/A
    Glad I found this thread! Since you said if removing the windshield cowl you might as well do plugs. I plan on installing f-sport lowering springs on my CT and they mention that you should remove the cowl. On top of that my car came from FL so the cowl is completely faded and I have a new oem replacement sitting in my basement. Figured while I do springs, I would install the new cowl... might as well be doing spark plugs to the list :).
    Nothing worse than taking something off then having to do it again because you could have done XYZ while that part was off...etc.

    Excellent info on the superseded spark plugs. Question. Since they run slightly hotter what exactly is the benefit to that?

    Thanks,
    -Nigel
     
  17. Mendel Leisk

    Mendel Leisk Underfoot

    Joined:
    Oct 17, 2010
    49,133
    35,037
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Less prone to develop deposits?

    If you've never removed the cowl before, video here about spark plug change (#13 IIRC) is informative. Mind-numbing amount of wrenching though. It takes me about 3 times as long.

    Sorry, forgot link:

    Nutz About Bolts Prius Maintenance Videos | PriusChat
     
    #17 Mendel Leisk, Oct 4, 2022
    Last edited: Oct 4, 2022
  18. NewShockerGuy

    NewShockerGuy New Member

    Joined:
    Sep 28, 2022
    16
    11
    0
    Location:
    NOVA/DC
    Vehicle:
    2016 Prius
    Model:
    N/A
    Awesome! Thank you for that. Doesn't look too bad but definitely looks like it makes the job easier removing it and since I'm replacing it no need to not get to the spark plugs. I have noticed that The denso plugs are the following: Denso 3499.
    spark plug.JPG

    These are about $9 per plug. I called the Toyota dealer by my house and they just quoted me about 22 per plug...ROFL.

    I checked the Toyota Part number on McGeorge (Had I known this I would have bought them when I bought the oil filter housing spin on ..)
    sparkplug2.JPG

    They have them priced at around $8.50 which is way more reasonable. I kick myself for not checking first now I'm going to pay double shipping...

    Ebay always has good prices on parts but anymore half the stuff is fake. I'd rather either get them from RockAuto or Toyota (but not my dealer cause they are wack with prices).

    -Nigel
     
    Mendel Leisk likes this.
  19. CR94

    CR94 Senior Member

    Joined:
    Dec 2, 2014
    2,132
    886
    0
    Location:
    Northwestern S.C.
    Vehicle:
    2011 Prius
    Model:
    Two
    I bought them from McGeorge in July for $8.95 apiece, plus tax and shipping
    Coincidentally, I lived within 2 miles of their store 1993-95, long before I owned the Prius..
     
  20. douglasjre

    douglasjre Senior Member

    Joined:
    Sep 13, 2008
    1,194
    439
    0
    Location:
    Orlando, FL
    Vehicle:
    2010 Prius
    Model:
    ----USA----
    Correction, everything on eBay is fake
     
Loading...