The best thinking on check engine light
Your brake pedal or wheel will vibrate when rotor surface issues are present. And, while we're on the subject of rotor surfaces, note that your brakes will squeal as you let up on the pedal when your brake wear indicators begin scraping against your rotors. Metal on metal scraping, indicating that your brake pads are completely worn away, makes a grinding or growling noise. In each instance, a trip to your brake repair shop is in order. Don't ignore the signs of brake repair.