3 of 3 people found the following review helpful
A long lasting plug that delivers decent power and economy,
December 2, 2009 C. Stone - See all my reviews
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This review is from: Denso (3422) SKJ16DR-M11 Iridium Long Life Spark Plug, Pack of 1 (Automotive)
These plugs came as stock with my vehicle when I bought it new. I noticed a 20% fuel mileage drop and checked the plugs. After 40,000 miles they were showed practically no wear and the gap had changed minimally. I ordered a new set of plugs anyway just to be sure. In the meantime I installed a set of Delco plugs, the difference was night and day. The Delco plugs ran too cold so the idle was rougher and there was a slight drop in fuel mileage on top of the original 20%. When the new Denso plugs arrived I installed them and indexed them as well (even though indexing plugs on a SUV probably doesn't improve perfomance too much). The difference was definitely noticeable, there was definitely more power and the fuel mileage went back to the original 20% drop that prompted this experiment. Since all other factors that could account for a mileage drop had been accounted for I attribute the drop to blended fuels. I came to this conclusion because while on a road trip I stopped at a fuel...Read more
(1 customer review)