Question posed on a TV newscast in DC.
"Q: When it's cold outside, should you let your car idle until it warms up or should you just start it and drive away immediately?
A: We went to car expert Pat Goss for the answer. Pat says the most efficient way to warm your car is to let it idle for one minute. Then you should drive your car gently until the interior temperature becomes comfortable. However, if there is a coating of ice on your car, you should let the car warm up for several minutes until you can de-ice your car."
