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Old 10-03-2012, 10:45 AM   #38
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What I Drive: 2003 Pitch Black ZTS Sedan

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Originally Posted by IH84DZ View Post
Yes. With your short trips which are not long enough for everything to reach nominal operating temperature, a best practice would be to let it idle at least 10 minutes before driving especially in temps below 50*F. Granted, you are burning fuel that isn't moving the odometer so fuel economy will go aren't really going to be impressed with your mileage if the car never gets warm enough for closed loop either.

Thermostat, hoses, moisture in the oil, the catalytic converter, oxygen sensors, fuel vaporization, transmission - all are systems that REQUIRE a certain temperature in order to operate properly. Systems designed to be heat cycled should be expected to fail early if not properly heat cycled. My professional opinion is that the extra $ spent on wasted gas as it idles (marginal amounts, really) will more than offset the cost and hassle that may result from inadequate heat cycling.
Noted - thank you so much for the info
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