
Lexus suggests to replace spark plugs every 60K miles due to EMISSION REGULATION!!! Now, I believe the original OE spark plugs in my F car should last at least 90K miles with almost perfect running results!!!



https://www.densoproducts.com/denso-3515-fk20hbr-j8-iridium-long-life-spark-plug



So, the new spark plugs did improve some performance in that very old M35. Please also be noted besides new spark plugs, I also clean the throttle bodies!!! (Why I also cleaned throttle bodies? That's because to replace the old spark plugs, I also had to remove the throttle bodies which were TWO, not one!!!























































































