2004 Mercury Sable GS 6 Cyl 3.00L
Why does my car shake and feel like someone is kicking the bottom of the car?
While driving my car, it intermittently shakes back and forth. It happens mostly when the car is idling. It continues to shake in reverse, neutral, and drive. It doesn't matter if you are on the brakes, and the shaking does not get worse if you try to accelerate. I recently had all of the spark plugs replaced about 4 months ago, so they are all brand new. What could be causing this issue?
Several possibilities; engine vacuum leak, air filter is clogged, spark plugs gapped incorrectly, faulty spark plug wires, faulty ignition coil, worn engine mounts - to list a few.