Spark Plugs Change or not at 60K?
07-24-20, 01:03 AM
#76
Lead Lap
07-24-20, 03:10 AM
#77
Intermediate
if gapped too small the flame kernel is too small to efficiently ignite the fuel. Gapped too big and the plug may not spark. Too big would be 0.070. With iridium plugs I lean toward gapping bigger to get a larger flame kernel. Iridium plugs dont wear out and so the gap remains constant its full life unlike copper plugs that gap bigger with time.
Turbo engines are gapped smaller to keep the flame from getting blown out and misfiring
the car was spec’d at 0.043” and it all about CAFE standards and performance.
Turbo engines are gapped smaller to keep the flame from getting blown out and misfiring
the car was spec’d at 0.043” and it all about CAFE standards and performance.
Last edited by Drcoffee; 07-24-20 at 04:21 AM.
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GR3Y5H3ART (07-26-20)
07-26-20, 01:56 AM
#78
Lead Lap
if gapped too small the flame kernel is too small to efficiently ignite the fuel. Gapped too big and the plug may not spark. Too big would be 0.070. With iridium plugs I lean toward gapping bigger to get a larger flame kernel. Iridium plugs dont wear out and so the gap remains constant its full life unlike copper plugs that gap bigger with time.
Turbo engines are gapped smaller to keep the flame from getting blown out and misfiring
the car was spec’d at 0.043” and it all about CAFE standards and performance.
Turbo engines are gapped smaller to keep the flame from getting blown out and misfiring
the car was spec’d at 0.043” and it all about CAFE standards and performance.
good info...from my understanding, usually most are Gapped correctly and i rarely have fiddle with gapping on spark plugs but if you are super thorough, measuring them doesn't take long at all
01-14-21, 03:15 PM
#81
Lol. I wasted my whole morning looking for which plugs I needed for an '18 IS350.
Turns out it's in the back of the Owners Manual...
In case you were wondering, it's Denso FK20HBR8 (3491)
Turns out it's in the back of the Owners Manual...
In case you were wondering, it's Denso FK20HBR8 (3491)
Last edited by nitroracer; 01-14-21 at 03:21 PM.
01-14-21, 04:47 PM
#82
2. Interesting, because for 2015 is350 plugs should be DENSO FK20HBR11.
After searching on denso website, it looks like the only difference between 11 and 8 is that 11 has 1.1mm gap, while 8 has 0.8mm gap. The rest of the specs are identical. So, it looks like last number in this case shows gap size in mm
https://www.densoproducts.com/denso-...ife-spark-plug
https://www.densoproducts.com/denso-...ife-spark-plug
Last edited by sunamer; 01-14-21 at 06:49 PM.
01-15-21, 08:03 AM
#83
If you check with Lexus, you'll see that in 2016, they switched to FK20HBR8, and I believe are still using that.
That would've been nice to know when I was shopping, since it appears Denso is facing a supply shortage. However, I was able to find some at Autozone with next-day pickup.
Last edited by nitroracer; 01-15-21 at 08:07 AM.
01-15-21, 10:34 AM
#84
If you check with Lexus, you'll see that in 2016, they switched to FK20HBR8, and I believe are still using that.
That would've been nice to know when I was shopping, since it appears Denso is facing a supply shortage. However, I was able to find some at Autozone with next-day pickup.
That would've been nice to know when I was shopping, since it appears Denso is facing a supply shortage. However, I was able to find some at Autozone with next-day pickup.
All these are for is350 models.
upd. I have just checked lexus manuals. So, for 2014-2017 they list FK20HBR11, while for 2018-2021 — FK20HBR8
Last edited by sunamer; 01-15-21 at 10:55 AM.
01-15-21, 02:00 PM
#86
so, I have just picked up Denso FK20HBR11 that I ordered yesterday (with a nice 25% discount) at advance autoparts, and a plug gap gauge. Guess what, despite toyota saying the gap needs to be 0.043, all six have their gaps between 0.038 and 0.039*, at least when measured at the center electrode. kinda interesting.
It would be interesting to know what the gap size for a new FK20HBR8 is.
upd. I did not remove a thin paper label on the back of the gap gauge prior to measuring. Correctly measured gap was pretty consistent between 0.040-0.041 for all 6 plugs
It would be interesting to know what the gap size for a new FK20HBR8 is.
upd. I did not remove a thin paper label on the back of the gap gauge prior to measuring. Correctly measured gap was pretty consistent between 0.040-0.041 for all 6 plugs
Last edited by sunamer; 01-16-21 at 09:49 AM.
01-16-21, 05:05 AM
#87
After getting new plugs I replaced them the same day. My 2015 is350 f sport RWD with 50720 miles is feeling a bit different right now. Old plugs did look uniform in terms of color, and electrode remaining life, but the main difference that was easily felt was when you lightly step on gas, the car has a bit less hesitation now.
So, is it worth changing spark plug at 60k miles? Absolutely yes.
So, is it worth changing spark plug at 60k miles? Absolutely yes.
01-16-21, 06:54 AM
#88
I checked lexuspartsnow and it looks like they only show FK20HBR11 version for 2014-2016 models, but then for 2017 to 2018 they list both FK20HBR11 and FK20HBR8 version as acceptable plugs for those models. 2019-2020 only show FK20HBR8.
All these are for is350 models.
upd. I have just checked lexus manuals. So, for 2014-2017 they list FK20HBR11, while for 2018-2021 — FK20HBR8
All these are for is350 models.
upd. I have just checked lexus manuals. So, for 2014-2017 they list FK20HBR11, while for 2018-2021 — FK20HBR8
There was no 2017 F-Sport, and double-checking the link from my last post, I do not see where FK20HBR11 can be substituted for FK20HBR8. I mean, obviously I'm going off the literal interpretation. I do not have enough automobile knowledge to know what is acceptable as a substitute, but for me, better safe than sorry.
01-16-21, 08:56 AM
#89
Sorry, I should've added that mine's an F-Sport variant.
There was no 2017 F-Sport, and double-checking the link from my last post, I do not see where FK20HBR11 can be substituted for FK20HBR8. I mean, obviously I'm going off the literal interpretation. I do not have enough automobile knowledge to know what is acceptable as a substitute, but for me, better safe than sorry.
There was no 2017 F-Sport, and double-checking the link from my last post, I do not see where FK20HBR11 can be substituted for FK20HBR8. I mean, obviously I'm going off the literal interpretation. I do not have enough automobile knowledge to know what is acceptable as a substitute, but for me, better safe than sorry.
01-18-21, 05:41 PM
#90
so, I have just picked up Denso FK20HBR11 that I ordered yesterday (with a nice 25% discount) at advance autoparts, and a plug gap gauge. Guess what, despite toyota saying the gap needs to be 0.043, all six have their gaps between 0.038 and 0.039*, at least when measured at the center electrode. kinda interesting.
It would be interesting to know what the gap size for a new FK20HBR8 is.
It would be interesting to know what the gap size for a new FK20HBR8 is.
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sunamer (01-18-21)