Ignition coils

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by AzusaPrius, Oct 9, 2025.

  1. AzusaPrius

    AzusaPrius Senior Member

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    Been wanting to try these and I finally placed an order since the timing was right.

    As soon as I took them out of the box I felt the weight on them and thought, I have to compare them and sure enough, there was added weight.

    These are designed with the primary and secondary windings at the top versus the standard style.

    The test drive went without a hitch,
    smooth all the way with a cold start and actually required less rpms to get to speed all while doing it faster.

    I was using Duralast ignition coils and there was nothing wrong with them and they have a lifetime warranty.

    Duralast weighs 183 grams each coil,
    while the new ignition coil weighs 220 grams each coil, a whole 37 grams more coppers windings than Duralast coils.

    No fit issue with the bigger coils either.

    Im just gonna run these for a while and see the change, which I already felt and saw on the average mpg display.

    These should run cooler with more power and last longer than a standard prius ignition coil. 20251009_110532-1.jpeg 20251009_110052-1.jpeg 20251009_111038.jpeg 20251009_112658.jpeg 20251009_115725.jpeg
     
  2. Brian1954

    Brian1954 Senior Member

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    How does the weight of the new brand X coils compare to an OEM coil?

    How much did you pay for a set of four of these brand X coils?
     
    #2 Brian1954, Oct 9, 2025
    Last edited: Oct 9, 2025
  3. Tombukt2

    Tombukt2 Senior Member

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    The trq red coils are similar .. and there's another CO that advertised heavily . The coils look heavy duty a lil fatter
     
  4. AzusaPrius

    AzusaPrius Senior Member

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    30 days in and my Carfax fuel tracker shows it going from 41.1 mpg to 43.3 mpg

    With no changes to driving style or roads.

    Im itching to disconnect my 12v and let it all learn from scratch with these but clearly they made an improvement in just 30 days.
     
  5. Hayslayer

    Hayslayer Active Member

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    41? Was it broken?
     
  6. AzusaPrius

    AzusaPrius Senior Member

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    Was it broken? (It?)

    No that was just my mpg at that time.

    Cold weather kills mpg and I live in the high desert and its only getting colder.

    Also I carry a lot of stuff for work and have an actual full size 15" OEM spare in the trunk and an aluminum front skid plate.
     
  7. Hayslayer

    Hayslayer Active Member

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    Based on your sig, you're a gimmick junkie. It's probably not the weather or what you carry in the car that causes your low mpg. We all have hobbies, do what makes you happy.
     
  8. AzusaPrius

    AzusaPrius Senior Member

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    @Hayslayer

    Yet I still find you in my threads providing nothing but jibber jabber.

    You dont know much if you do not think added weight to your vehicle and cold weather cause bad mpg...I didnt even mention that I drive it like a race car.
     
  9. Hayslayer

    Hayslayer Active Member

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    Hmm....I'm confident I have adequate knowledge on the subject. Also have enough knowledge to not say that weight and cold weather don't affect mpg, yet also know that you're assigning blame for your "low" mpg where you "want" to assign it, not necessarily to the true root cause.. Looking back at some of "YOUR" threads, with all the "upgrades" you've installed and all the improvements you "feel" shouldn't you be at 100mpg and running 9 second quarter mile times or competing in Nascar while you "drive it like a race car"?
     
  10. AzusaPrius

    AzusaPrius Senior Member

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    @Hayslayer

    You literally say it in post #7

    You are coming off as the malice stalker type.

    9'ish most likely for sure...

    I drive it fast to shame other cars and watch them in the rearview mirror.
     
  11. Hayslayer

    Hayslayer Active Member

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    Struggle much with reading comprehension?

    9ish? When strapped to one of Elon's rockets?
     
  12. AzusaPrius

    AzusaPrius Senior Member

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    Well I am not selling anything to you.

    This is just my observation and experience with my car.

    You seem to have a learning curve so I will show you these two images, that show the difference between the coils.

    Toyota has even changed their coils to these typese in their new gens.

    All Im saying is that I have not changed my driving style or roads taken and mpg is going up.

    Take out all my gear and aluminum skid plate and I would get more mpg than you could and it would be easy.

    First image shows how my new coils are designed.

    Second image shows how all other standard pencil style coils are made.

    This is not a "sales pitch" Im playing
    "Gate Keeper" on these... Screenshot_2025-11-15-08-42-36-1.jpeg Screenshot_2025-11-15-08-42-56-1.jpeg
     
  13. ChapmanF

    ChapmanF Senior Member

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    Is one of those designs better than the other? What makes it so?
     
  14. AzusaPrius

    AzusaPrius Senior Member

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    @ChapmanF

    The main idea is to prevent high heat degradation of the primary and secondary windings.

    Moving both of them to the top of the coil will keep them cooler and provide a longer lasting coil.

    Another benefit to doing this, is the ability to provide 30% more windings providing better power to the spark plug.

    That is why the new coils weigh more than my other coils.


    They just provide better power that is more consistant than stock through out the power band and engine is not as loud.

    Getting to cruise at 50-60 mph @ 1000 rpms is a lot smother and easier.
     
  15. Hayslayer

    Hayslayer Active Member

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    I can't read anymore of this, or I'll puke from laughing so hard. I wish you the best of luck in all your endeavors.
     
  16. ChapmanF

    ChapmanF Senior Member

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    Do you have a log of your OBD misfire margins under different driving conditions with the old and new coils?

    When a coil/igniter assembly fails, what has usually failed?
     
  17. AzusaPrius

    AzusaPrius Senior Member

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    @ChapmanF

    I was not having misfires at all and wanted to try these coils out, even though my coils were fine and have lifetime warranty.

    My engine was louder and a bit slower and losing mpg before the swap of coils.

    Now its quieter and gets to 50-60 mph quicker and I can drop my rpms down to 1000 at that speed no problem and so my mpg is going up.
     
  18. AzusaPrius

    AzusaPrius Senior Member

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    Now the primary and secondary are in the GREEN, outside and above the valve cover.

    Versus being in the RED inside the cylinder walls.

    The old style is why many coils went bad before their time.

    Also they are able to have more copper in the primary and secondary because of the new design, which gives better power. Screenshot_2025-11-15-12-03-22-1-1.jpeg
     
  19. ChapmanF

    ChapmanF Senior Member

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    The nice thing about the ECM computing misfire margins is the chance to know whether anything is coming close to misfiring or incomplete firing under any driving conditions.

    Given that there isn't anything else the igniter / coil / spark plug are responsible for, the margins could be of interest to a person wanting to compare them.
     
    Brian1954 likes this.