Worked on my mini jet boat build today, then took my grandma to her Dr. appointment, and then shopping. While downtown stopped and got spark plugs, air filter, oil, and oil filter for the neighbors tacoma i worked on yesterday, some. I'll change those tomorrow for her. I pulled out 2 plugs yesterday just to look at them, 1 was a Denso copper, and 1 NGK iridium, both looked worn, especially the Denso. Since it now runs warmer and won't stay in cold rich running fuel mode it should use less gas to, and new plugs are way overdo, as is that filthy air filter. Matching NGK iridiums, properly gapped, should help her gas mileage some more. She told me that its hard on gas, much worse than she expected it to be. She bought it in April 2022 from a private seller, and it doesn't seem like the guy took very good care of it.
And who mixes spark plugs? It would drive me insane if I knew that my truck had a mixture of brands, and types of plugs in it. Maybe I am just too picky, or not.