1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Spark plug change interval

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Maarten28, Jan 28, 2019.

  1. Maarten28

    Maarten28 Active Member

    Joined:
    Jul 13, 2014
    414
    223
    1
    Location:
    Netherlands
    Vehicle:
    2011 Prius
    Model:
    Three
    In the USA the recommended interval to change spark plugs is 120,000 miles. In Europe it is 90,000 km (56,000 miles).
    Does anyone have any insight in this massive difference? And do people in the USA actually change them only every 120,000 miles or do they (need to) do it more often? 56,000 miles is already a long interval, I suppose the use of iridum plugs (which are also recommended in Europe, Denso SC20HR11 is mentioned in the owner's manual) is what makes this possible?
     
  2. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,476
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    Iridium plugs are the reason ;).

    I have been pooling my plugs with egr circuit cleanse as the windshield wiper cowling comes off and it makes the plug job 10 minutes :).

    I’m doing the circuit cleanse every 50k miles or so, which means the plugs will be every 100 k miles after their original change at 120k miles;).

    Hope that helps(y).
     
  3. Maarten28

    Maarten28 Active Member

    Joined:
    Jul 13, 2014
    414
    223
    1
    Location:
    Netherlands
    Vehicle:
    2011 Prius
    Model:
    Three
    Well, Iridium plugs are also what's used in Europe, so that doesn't explain the difference in the interval. I've had a look at a US manual for 2011 and it lists the exact same spark plug as the European manual.
     
    Mendel Leisk and Raytheeagle like this.
  4. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,476
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    Gas quality?
     
  5. royrose

    royrose Senior Member

    Joined:
    Mar 21, 2009
    1,389
    948
    4
    Location:
    Foot of Pikes Peak
    Vehicle:
    Other Hybrid
    Model:
    Limited
    To further confuse things: In small print in the 2010 ,2011 and 2018 maintenance manuals it says that the spark plug replacement interval for California and some other states the interval is 150,000 miles. I haven't looked at other years.

    In the Rav4 hybrid and gas versions the interval is 120,000 but only says that changing plugs is required for the emissions control warranty, not that the interval is different for California.
     
    #5 royrose, Jan 28, 2019
    Last edited: Jan 28, 2019
    Maarten28 likes this.
  6. tonynap

    tonynap Member

    Joined:
    Jan 13, 2019
    43
    37
    0
    Location:
    NY
    Vehicle:
    2012 Prius
    Model:
    Two
    I just replaced the plugs with the original (SC20HR11). At 132,000 miles they came out looking great.
     
    Maarten28 likes this.
  7. Fostel

    Fostel Member

    Joined:
    Oct 30, 2018
    87
    25
    0
    Location:
    London
    Vehicle:
    Other Hybrid
    Model:
    Excel
    I planned to replace mine at 75,000 miles because I experienced a few rough, cold start ups.
    It may be the whole EGR and intake thing, unfortunately...
    No oil catch can yet.
     
  8. ThatDudeOrion

    ThatDudeOrion Member

    Joined:
    Dec 2, 2016
    95
    86
    3
    Location:
    Central, NJ
    Vehicle:
    2011 Prius
    Model:
    Three
    For me, the rough cold starts seem to happen most often/worst after I push the on/off button while the ICE is still running. I saw it mentioned here on PC somewhere that it's best to wait for the car's computer to shut the ICE of manually and then power down via the on/off button. I have tried to follow this whenever possible and I personally believe it has reduced/eliminated the incidents of the rough startup.
     
    Fostel likes this.
  9. Maarten28

    Maarten28 Active Member

    Joined:
    Jul 13, 2014
    414
    223
    1
    Location:
    Netherlands
    Vehicle:
    2011 Prius
    Model:
    Three
    Interesting observation!
     
    Fostel and ThatDudeOrion like this.
  10. Rebound

    Rebound Senior Member

    Joined:
    Mar 11, 2010
    3,961
    2,609
    0
    Location:
    Portland, OR
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    It’s either that, or you get the rough startup if you switch off before the engine completed warmup. But if the engine is warmed up, it won’t be running when you switch it off.

    I had this issue with my 2010 Prius. I sold that car in 2012 and bought one of the first Plug-in Prius cars, and it doesn’t have the problem. So Toyota fixed something in 2012.
     
    Raytheeagle and ThatDudeOrion like this.
  11. ThatDudeOrion

    ThatDudeOrion Member

    Joined:
    Dec 2, 2016
    95
    86
    3
    Location:
    Central, NJ
    Vehicle:
    2011 Prius
    Model:
    Three
    Mine is a 2011, so it's entirely possible. If they hadn't fixed it with whatever they did in 2012 I'd almost like to be able to turn the switch off and get out lock the car etc. with the ICE still running and then have it shut itself off when the right conditions were met, similar to a turbo timer.