It's interesting that in older non-computerized cars, the A/C would *lower*
the idle rpm, thus conceivably *saving* gas at idle!
In newer cars, the A/C bumps up the idle speed, indeed costing more gas.
'pyooters, donchaknow....

Idling in winter w/ the heaters on can conceivably lower engine temp.
Ackshooly does help if the engine is *over*heating.

What gets me is the new thing of driving off w/o warming up the car at all,
as per, sposedly, mfr's instructions!
----------------------------
Mr. P.V.'d
formerly Droll Troll
"mac" > wrote in message
oups.com...
>I used to think idling (maybe more than 5 min) was bad for engine, but
> then I read elsewhere that it's no worse than driving. I think i read
> that idling with AC on puts alot of stress on the engine. Is this
> true? Should I turn off the AC if idling for more than 5 minutes? I
> have a dodge truck, and ideally I could sit in it for 15 minures,
> idling, with AC on...
>
> Also, in the winter, is idling with heat on any problem?
>