Ever felt your car shaking or vibrating while sitting at a red light? That rough idle is a classic symptom, but the cause isn't always obvious. As shown in the comparison, 2015 car vibrating at idle, RPM 500 WHY YOUR CAR SHAKES WHEN IDLING If your car feels smooth while driving but starts vibrating or shaking at a stoplight, something isn't right. At idle, the engine runs at its Is your car vibrating when idle? Here's when you should be worried Shaking and vibration while idling. What's causing it? 8 Reasons Why Your Car Vibrates When Idle In The Garage with CarParts.com