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

Spark plug replacement

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Lodrun, May 4, 2011.

  1. Lodrun

    Lodrun My proper car is an MGC

    Joined:
    Feb 18, 2010
    21
    3
    0
    Location:
    Cheltenham
    Vehicle:
    2007 Prius
    Model:
    N/A
    My UK Prius is 4 years old with 40,000 miles on the clock. The service book says replace the spark plugs every 4 years/60,000 miles. Do I need to change them now or will they last? It runs fine at the moment.
     
  2. seilerts

    seilerts Battery Curmudgeon

    Joined:
    Mar 7, 2010
    3,326
    1,512
    38
    Location:
    Santa Fe, NM
    Vehicle:
    2005 Prius
    Not sure what they would put in yours, but iridium plugs last a very, very long time. In the US, the service interval is 120,000 miles.
     
  3. 2009Prius

    2009Prius A Wimpy DIYer

    Joined:
    Mar 25, 2009
    2,705
    509
    63
    Location:
    USA
    Vehicle:
    2009 Prius
    Really strange the same spark plug would have different life in different regions. :confused:
     
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

    Joined:
    Mar 8, 2008
    18,198
    6,461
    0
    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    Well, why is it that the US Prius has a 120K mile change interval in much of the country, but a 150K mile change interval in CA and other PZEV states? I suspect the latter change interval was established more for regulatory reasons and less for engineering reasons. I don't believe that the gasoline quality in the PZEV states (besides CA) is notably different from non-PZEV.

    Since the engine ECU will tolerate ~25% misfire before logging the misfire DTC P030x, I would err on the side of replacing the spark plugs sooner vs. later (my personal practice is to replace at 100K miles.) Seems silly to have unburnt fuel heating up the catalytic converter.
     
  5. J.Wilkie

    J.Wilkie 80 Mile Daily Commute

    Joined:
    Nov 12, 2005
    157
    2
    0
    Location:
    Behind The Orange Curtain
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Advanced
    Did mine at 100k too. No issues.
     
  6. stefano5777

    stefano5777 Member

    Joined:
    Mar 15, 2011
    380
    47
    6
    Location:
    St. Petersburg Florida
    Vehicle:
    2005 Prius
    Model:
    N/A
    I changed mine at 100k as well with no issues and to be honest plugs still looked good.
     
  7. F8L

    F8L Protecting Habitat & AG Lands

    Joined:
    Aug 14, 2006
    19,011
    4,080
    50
    Location:
    Grass Valley, CA.
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    At 120k my plugs looked good. They car maybe have ran a bit smoother after the change but it could just be my imagination.