Why does the car shake when idle and jerk when braking?

Car Idling Low

I had this same problem.

I am guessing what you mean is that the car is shaking.

If you look at your RPM's on your car you will see that it is a low lower than it normally is.

For my car it idled at around 400 RPM's ( which is very low)

Depending on your car it can idle at a variety of different RPM's

This problem started happening to me when I changed my 02 Sensor.

Solution:

Go to an auto shop and have them scan your car with one of their sensors that gives you an error code on what's wrong.

google that code or see if they can look it up while they are there.

If it is the 02 sensor then you need to replace it.

Mine cost me about 60 bucks.

After I replaced my 02 sensor it fixed my cars idling problem.

The first time I replaced my 02 sensor is what gave my car the problem.

After I replaced for the second time it went away.