Denso vs. NGK 4912 Spark Plugs? Are Amazon or Rock Auto problematic for 'fakes'?

Discussion in 'Gen 3 Prius Technical Discussion' started by davekro, Feb 4, 2026 at 1:48 AM.

  1. davekro

    davekro Active Member

    Joined:
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    Vehicle:
    2013 Prius Plug-in
    Model:
    Plug-in Base
    I was wondering if it was worth it to consider using an equivalent spec'd NGK 4912 (ILKAR7B11) vs. the OEM choice of Denso SC16HR11(Toyota p/n 90919-01275)?

    Although Rock Auto lists four different NGK part numbers for the 2013 Prius, Chat Gpt says only the NGK 4912 (ILKAR7B11) matches the Denso/ Toyota Spec. and is of equal quality to the Denso SC16HR11. I understand that Chat Gpt, can make mistakes. But what seems to be the consensus of this NGK plug being of equal quality as the Denso?

    On Rock Auto, I see four different NGK Spark Plug part numbers listed as compatible for the 2013 Prius.
    NGK 4912 {Alternate Inventory Numbers: ILKAR7B11} $5.89 (O'Reilly's price $23.99! :eek:O )

    NGK 92274 {Alternate Inventory Numbers: LKAR7AHXS} $9.47
    NGK 93501 {Alternate Inventory Numbers: LKAR7BIX11S} $6.58
    NGK 94297 {Alternate Inventory Numbers: LKAR7BGP} $5.38

    Rock Auto- DENSO 3499 {Alternate Inventory Numbers: SC16HR11} $10.39
    O’Reilly’s and Autozone local stores Denso 3499 $17.99

    toyota.oempartsonline.com Lists Spark Plug - Toyota (90919-01275) for $14.49

    So, is the $5.89 NGK 4912 just as good as the $10.39 Denso at Rock Auto?
    Any worries of getting a 'fake' Denso from Rock Auto?
     
  2. Hayslayer

    Hayslayer Active Member

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    Vehicle:
    2009 Prius
    Model:
    Touring
    I use RA quite frequently and have purchased dozens of sets of Denso plugs. Never had a counterfeit.

    Many people believe a spark plug is just a spark plug, but I also know I've never had a skip or miss after installing a new set of Denso plugs in a Prius.