what's worse for the engine?

[austinnp]

my girlfriend keeps nagging me because whenever i get out of the car for like 5 minutes she says i have to shut it off because its REALLY bad for the car just to sit there and idle

i always thought that starting the car put more strain on the engine for one and used more gas than idling for a few minutes

either way im not really convinced leaving the car running for a few minutes is that bad for it, can someone who actually knows end this debate?

thanks

[Zgringo]

As long as you have oil pressure and a good cooling system you won't have a problem, and by shuting it off for a few minutes only cycles the started more often.
Now running without a air cleaner or changing the oil is worse for the engine.

[slideways...]

it wont hurt the car to let it idle for 5 minutes or 500 minutes as long as its in otherwise good shape.
starting the car doesnt put very much strain on the engine, just mostly on the starter and flywheel.
starting the car uses nearly no extra gas because it only cranks a couple times before it starts up.

[AlmostStock]

Originally Posted by austinnp

my girlfriend keeps nagging me because whenever i get out of the car for like 5 minutes she says i have to shut it off because its REALLY bad for the car just to sit there and idle

i always thought that starting the car put more strain on the engine for one and used more gas than idling for a few minutes

either way im not really convinced leaving the car running for a few minutes is that bad for it, can someone who actually knows end this debate?

thanks

Your girlfriend is right. If you get out of the car and leave it running that can be very bad for it.

Someone can jump in and drive off.

[DRW1000]

Not to mention the unnecessary damage to the environment. An idling car is getting 0 mpg shutting it off for 5 minutes saves that fuel.

[MagicRat]

idling a car is a little hard on the camshaft but otherwise is okay. However, I would shut the car off if its going to idle for more than 1 minute or so

[curtis73]

Idling it is fine for a few minutes. It puts very little stress on the rings, bearings, and valves. It does (like MagicRat said) very little for upper engine and cam lubrication. Not a big deal if you just stopped from going somewhere and the car is warm. Not so smart for just starting up and letting it idle cold. Oil dilution and cam wear can happen.

Tell your girlfriend to (politely) stick it. At least you'll still have your car.

[siege911]

[AlmostStock]

Originally Posted by curtis73

Tell your girlfriend to (politely) stick it. At least you'll still have your car.

His girlfriend was the one who said to shut it off so I guess he's the one who has to stick it!

Actually everyone is right. Idling a few minutes or restarting won't hurt anything. Cars are designed to handle either without any serious consequences. I bet it would be hard to measure the difference.