Engine Shudder

[UTVitz]

Interesting you say it has developed the shudder. Mine has done it since new, which mostly occurs during a/c cycling, but can happed as the idle adjusts after coming to a stop. Unless it starts to stall the car I wouldn't worry about it, try a different brand of gas. I've only ever used Chevron in this car and it's always happened, not all the time, not every day, just sometimes.