if you fail emissions theres a 99.999% chance its not your plugs unless they have 300k on them or they were physically damaged, in which case you have much bigger issues.

 

If nothing is wrong, I don't see any reason why anyone would replace the spark plugs. Again, this is just my opinion. Unlike other wear and tear items that do impact the driving experience, such as brake and filter. Just because your car reaches whatever miles is not a good reason. And if the spark plug does fails, usually you will see engine light/code. Again. this is just me.

 

I think most constructive people in this forum like to do preventive maintenance before something goes "wrong". Why would anyone wait until an engine air filter is totally clogged and you get a light/code that the engine is starving for air before replacing it? As for changing spark plugs: The warranty manual wants you to change them at 60,000 miles or 6 years for emission warranty purposes. IMO this is BS. These plugs are good for at least 100,000 miles.
Nobody here as yet has stated that they failed an emission test with old spark plugs. Never.

 

Yeah.....I did mine at 60,000 and they looked to be in great shape. I am sure that I could have waiting until at least 120k.

It was just a job that was cheap to do and relatively easy on the new FKS.

 

Plugs are a wear item and you def don't want to wait until something is wrong lol. these plugs last 100-120k and i think that's very reasonable.

 

Good post from supratreo. The number of miles is hit and miss. In my humble opinion I would say no more than 115,000 miles. So you change the plugs once in the life of your car. What's the big deal?

 

im glad I found this. I thought my dealer (which is under new ownership) was trying to gouge me, as I never dreamed I’d need new plugs (2020 Rx350, 26k miles) bought 6 years ago.$1,330! Seems like it’s a standard somewhere - is this a Lexus published schedule or something dealers made up? But still feels wrong.