What does idle mean on a car?

I don’t understand what’s happening under the hood when I idle. What does idle mean on a car?

Bonnie Stinson · Updated on
Reviewed by Shannon Martin, Licensed Insurance Agent.
Good question! The basic definition of idling is when your engine is running but the vehicle is not moving.
When your vehicle is idle, it means that everything is powered on. Technically speaking, it could move at any moment, although it’s in a neutral gear.
When is idling bad? Idling in parking lots is prohibited by many schools and businesses since emissions are bad for the environment. You emit a ton of exhaust when you stay in the same place without moving. The term “idling” usually means that you are running your engine unnecessarily for a prolonged period of time.
When is idling good? Idling can help you charge your battery or warm up the engine in cold weather. In some situations, it’s important to idle the car for a few minutes before driving.
Excessive idling is not good for a vehicle, however. Idling means that your engine cannot reach peak temperature. So, fuel is only partially combusted and begins to build up residue on the cylinder walls. This could damage the spark plugs, cylinders, and exhaust system.
Hope this was helpful!
While you’re being a responsible car owner, now is a good time to double-check your
car insurance
coverage. If you suspect you might be overpaying, why not try
? The app (or our friendly agents) can help you compare rates and find a better policy. You may not even have to sacrifice coverage to save money!
View full answer 
Jerry partners with more than 50 insurance companies, but our content is independently researched, written, and fact-checked by our team of editors and agents. We aren’t paid for reviews or other content.

Join 4M+ members in lowering their car insurance

Easiest way to compare and buy car insurance

No long forms
No spam or unwanted phone calls
Quotes from top insurance companies
Find insurance savings