8 Best Spark Plugs for Fuel Economy (September 2026) Honest Reviews
I noticed my daily driver sipping a lot more fuel than usual last winter. The engine had rough idle, sluggish acceleration, and the check engine light kept flashing misfire codes. After swapping in a fresh set of iridium spark plugs, my truck gained back roughly 2 MPG on the highway and the misfires vanished. That … Read more