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

4th Gen Spark plugs alternatives

Discussion in 'Gen 4 Prius Main Forum' started by Kasra, May 28, 2023.

  1. Kasra

    Kasra Member

    Joined:
    Mar 10, 2018
    48
    27
    0
    Location:
    Irvine, CA
    Vehicle:
    2015 Prius
    Model:
    Four
    Has anyone used a different spark plugs than the ones recommended?

    I just added a 2020 Prius LE, with 145K miles, to my collection. I looked at the Owner's manual and it seems like that Toyota only listed Denso 3517 (FC16HR-CY9) as the only option, so that's exactly what I purchased. When I took the plugs out, I noticed that they are NGK 9029 (DILKAR6A11). I checked the two plugs side by side and it's a perfect fit. I was getting +70 mpg on the NGKs that I took out, but I have to test the originals (Denso) to see what I get.

    It looks like the heat rating and the gap size are different, however I didn't find any issues with the smoothness or start/stops. I would like to get some opinions here.
    20230528_094956.jpg
     

    Attached Files:

  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,132
    50,049
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    it's important to go with oem, and buy from a dealer, as there is a huge market of counterfeits
     
  3. Mendel Leisk

    Mendel Leisk EGR Fanatic

    Joined:
    Oct 17, 2010
    56,671
    39,221
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Probably previous owner changed them with the NGK at 120K.
     
  4. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

    Joined:
    May 12, 2018
    7,427
    6,913
    1
    Location:
    Pennsylvania
    Vehicle:
    2018 Prius c
    Model:
    Two
    NGK builds a fine plug, but I'd always use the Denso if they were available.
     
    Kasra likes this.
  5. ColoradoBoo

    ColoradoBoo Senior Member

    Joined:
    Jul 19, 2019
    1,042
    682
    4
    Location:
    Monument, Colorado USA
    Vehicle:
    2017 Prius
    Model:
    Two
    Yep plugs are, probably, the most counterfeited item out there...one of the few things I'll only buy from my Toyota dealer.
     
    Pulse07 and Kasra like this.
  6. BiomedO1

    BiomedO1 Senior Member

    Joined:
    Mar 27, 2021
    1,834
    929
    0
    Location:
    SacTown, Ca
    Vehicle:
    2021 Prius Prime
    Model:
    LE
    Both Denso and NGK plugs are excellent spark plugs. 40+ years ago when Denso (Nippon-Denso) first came here to the states; they were junk. Blew-up quite of few race car engines. They fessed up and paid for those engines and are now at the top of the food chain. I used to work the parts counter at Grand Auto Parts here on the West coast. Saw a lot of this, first hand.
    Stay away from the Champions and Bosch ... I think they are still junk; don't last.
     
    Kasra likes this.
  7. Pulse07

    Pulse07 Active Member

    Joined:
    Feb 24, 2020
    273
    139
    0
    Location:
    East Bay, California
    Vehicle:
    2020 Prius
    Model:
    XLE AWD-e
    Oem Part # 90919-01298. I would buy from a trusted dealership to avoid counterfeits on amazon or ebay.
     
  8. ColoradoBoo

    ColoradoBoo Senior Member

    Joined:
    Jul 19, 2019
    1,042
    682
    4
    Location:
    Monument, Colorado USA
    Vehicle:
    2017 Prius
    Model:
    Two
    Speaking of spark plugs, my daughter didn't get maintenance info when she bought her used 2012 Toyota Sienna XLS van a few years ago so I've been replacing all fluids and doing maintenance as we get the time. (She's a busy Momma!)
    So I was FINALLY able to get the van in my garage Saturday and, since it's a V-6 2GRFE engine, you have to remove a bunch of stuff, including the exhaust manifold, in order to reach the 3 plugs in the back. The van had 163,000 miles so plugs were overdue on both years (10-years) and miles (120,000) but I was hoping the previous owner had changed them. NOPE....they were TIGHT when removing and also had a little yellow "X" on top of the plugs...which is what they have when installed during factory production.
    Some notes to folks swapping out spark plugs:
    -Try to take them out when the engine is warm, not hot and, definitely, not when it's cold. (Toyota loves aluminum engines.)
    -Starting with the ignition coils' 10mm plug ONLY use hand tools...power tools and old plastic don't play well together...it's not a race!
    -When removing the clip from the top of the coil, do NOT squeeze it...use a pick to lift up the tab on the inside while pulling on it with the other hand. On older cars, this can be tricky. (The #5 plug in the Sienna was a bear...took me quite a while to get it to come lose...ended up lifting up the tab with a 90-degree pick with one hand and used a long flat-head to gently pry it lose so it would come off.
    -After pulling out the coils, look inside of them to make sure the little spring is still inside of them...rarely, but sometimes, they will stick to the top of the plug and you have to get them out else they could slide when into the engine when removing the plugs
    -When inserting new plugs, do it by hand and screw it only a few turns before coming back out...making sure you do not have the threads cross-threaded.
    -Plugs are a critical item so need torqueing. (2GRFE engines' plugs are torqued to 13 ft/lbs.) Sometimes it can feel like you are going too tight but just be patient, it's pretty scary you're first time. Have a GOOD torque wrench, too! TIP: There's usually a bolt on top of the front section of the car and I'll test the torque wrench with that before using on the plugs....just gives me peace-of-mind!)

    Oh, if you DO break a clip that goes on the ignition coil, you can, temporarily, wrap it with electrical tape to hold it (and some people use a zip tie...there's a few youtube videos on that) but you'll need to replace that clip. (Some will just splice the wires but you can, also, use a little pick to remove the old one and then insert into the new one.)

    I'm so thankful I didn't break any clips but had 6 spares on-hand just in case. Oh I forgot to mention, it's a good idea to go ahead and replace the PCV valve while you're in there.

    After doing the job an re-connecting the negative battery terminal, the Sienna had a very hard time starting....just turned and turned. I've heard this can happen when doing this job so didn't freak out too much. (I just re-checked ALL connectors I had disconnected and prayed I didn't leave one of the ignition coil clips off on one of those back 3 plugs.) Oh, I also cleaned her throttle body GOOD while I had it at, front and back...quite a lot of crud in there. So I pumped the gas a few times she started right up. It does take the computer a good while to re-calculate all of the settings so it might run rough for a bit. I drove her down to refill the tank and, since that first time, she started on the first try.

    Later that day, my daughter texted and said the van ran MUCH better and that it even sounded "turbo charged" when it first starts up, now. (She's funny)
     
    #8 ColoradoBoo, Jun 12, 2023
    Last edited: Jun 12, 2023