Things like that happen just because the car isn’t running quite right for some reason - and there are lots of reasons. So your post doesn’t contain enough information for anyone to even begin to think about it.
What year is the car? How many miles? Is there a check engine light on? What is the condition of basic maintenance items - spark plugs, wires, fuel & air filters? Is the temperature gauge behaving normally? Has it been to a mechanic for this or anything recently? If so has anything been checked, tried, etc.