ignition system maintenance

⚡ Quick Answer: Bad spark plugs cause: ❌ Engine misfires (P0300–P0308 codes) ❌ Rough idling (vibrations at stoplights) ❌ Poor fuel economy (reduced MPG) ❌ Hard starting (cranking but not firing) ❌ Check engine light (often flashing) Check for: Electrode wear, carbon buildup, or oil contamination. Replace every: Copper: 30,000 miles Platinum: 60,000 miles Iridium:…