Which Spark Plugs?! Denso SC20HR11, SC16HR11, or IXEH20TT??

I'm currently using the new 44's and they feel fine. I think it's because I have a bad egr, but my car just started throwing misfire codes....i know more by next week

 

I'm interested in the recommendations from other users since it's been bothering me too

Mi MIX 2S ?

 

what are the oems?

 

I replaced the plugs week before last, holding my Official User Manual open to the page listing the spark plug part number. If it worked to 135,000 miles without a problem with the SC20H11, why risk fate with a different part? Now, had it been a later model Prius that called for the hotter plugs, or if the SC20H11 was Manufacture Discontinued (which it wasn't at Advanced Auto), then I'd have a different answer.
But I have a lot less angst about this kind of thing after replacing the plugs. The ones I took out were good looking (tan on the ceramic) and, while a bit worn, the gap was still pretty close. Compare this to my olde '71 VW Beetle which needed new plugs every 12,000 miles, not to mention distributor points and condensor, and everything had to be checked and re-gapped at 6,000 miles. And a new distributor every 50,000 miles or so because the distributor shaft would get wobbly on its bearings.. The Prius is a dream by comparison, despite having to take out the windshield wipers to do the work .

 

These are the ones for the '10 that has the iridium on the ground electrode also, looks like the original plugs.

https://www.rockauto.com/en/moreinfo.php?pk=6276843&cc=1444360&jsn=369&jsn=369

 

i wonder if and when toyota made the switch, and if any members have seen the new plugs in their cars?

 

No they don't. A spark is a spark. You have been brainwashed.

Unless one kind of plug somehow somehow sends some of the voltage somewhere else besides into the spark, all of the claims about superiority are just marketing hype.

And you need to understand what a "hotter plug" really is.
That does NOT mean that the spark is hotter.
It means that the design keeps the electrodes at a higher temperature; the spark is exactly the same.

You only need a hotter plug if what you have now tends to foul with carbon.

Having the electrodes run at a higher temperature might actually create a "hot spot" that contributes to compression pre-ignition and loss of power and potential engine damage.

 

I thought these were the correct plugs so I ordered a set and installed at about 145,000 miles, just after 180,000 miles I started having intermittent misfires. I put the original plugs back in and no more misfires. The original plugs now have another 9,000 miles on them and still doing fine. The plugs that are listed as the right ones are iridium, but have a platinum ground electrode and didn't hold up.

https://www.rockauto.com/en/moreinfo.php?pk=1293084&cc=1444360&jsn=369

 

Me thinks Toy is spec-ing the hotter plug in hopes they will burn coolant better...

Based on how basically brand new my 2010's plugs looked at 120k miles, I'll stick with the 20's when it comes plug time for my 2014. The last thing these engines need (in my opinion) is a plug which may contribute to pre-igntion compounding the EGR issues. Sheesh...

 

Maybe you need the hotter plug to avoid plug fouling after the oil consumption reaches Toyota's "normal" rate of 1liter/1000km? Or earlier, if doing mostly short, low-speed trips? They must've found a problem with the 20s in some undisclosed circumstance.

 

Any updates on this?
Did everyone switch to SC16?
That's what Toyota dealership is offering me.

Thanks.

 

I think I recall reading that the 20's were being phased out by Denso, replaced by the 16. Reading between the lines in the Denso literature, seemed that plug was almost exclusively for Prius?

I'd go with the 16's.

My Canadian schedule says for the spark plug replacement: replace at 120 mo / 160000 km, thereafter every 60 months / 80000 km. For me the 12 years will come first, will see how that goes.

 

I actually get a little predetonation (knocking) in my 2011 Prius Two, ....lesser with Premium Top Tier gas, but still present. I wonder if it would help me to go to go one step colder than the 20's?

 

How many miles on it? By "premium" you mean higher octane selection?

Toyota now recomends the Denso ...16, which is hotter. Pre-ignition, detonation, are caused by carbon build-up in the cylinder head, which, if I'm not mistaken, means you should be going to hotter plug.

 

I replaced the 20s with the 16th on the 12th of January and I have noticed any difference.

 

NO.
You need to find out what the cause is.....and not just throw guesses at it.
The only way this will help is if the present plugs are caked with carbon, in which case you probably need HOTTER ones.

 

In case it's not clear: a "hotter" plug will burn off carbon deposits better, and it's carbon build-up that causes pinging, little glowing carbon nodes igniting the charge early.

 

There are posts here with people using non own plugs and experienced lower than their average MPGs. Once they put the old OEM plugs back in, mpgs went back to normal. It prompted them to buy oems, once the new oems were in, MPGs were same as the old oem plugs. So sparks were are different, so spark isn’t just a spark.