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I will be away for all of January and February. Should my car be driven every so often to keep it running well or can I just leave it in the unheated garage for the duration? – Sandra

Having someone run your car while you're away would be ideal. If that's not possible, there are measures to ensure it will start when you return.

When a vehicle sits for an extended period, battery drainage is a concern.One option is to disconnect the battery – but there are downsides. "There's a term called 'airport flat' for batteries – which is because people go away and leave their cars at airports. It means the battery is so dead there's not even a minute trace of electricity left in it," says Ken Cousin, associate vice-president of BCAA Road Assist. "And two things can happen: one, your radio will lose all its memory and any other settings you have. Second, your car will somewhat forget how to run properly, depending on the car. The computers have to relearn.

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"So if you disconnect the battery, expect the radio settings and things like that to be gone, and also expect your car, once started again, to perhaps run a little rough for a short time while the computer systems relearn your environment."

Cold-weather experts recommend using a trickle-charger to keep the voltage topped up. However, the battery must be good to begin with. If there's an opportunity to have someone drive your vehicle once a week, that's also advised.

"It keeps things like brakes moving, and keeps rust from forming on the rotors and so forth. The battery maintainer will make sure the battery has a full charge and the car will start," says Paul Datzkiw, manager of Beverly Tire and Automotive in Hamilton, and former technical supervisor at CAA South Central Ontario. "But to keep things moving and lubricated at the top end, you want to get the vehicle up to what's called normal operating temperature and maintain that for a period of time.

"All vehicles today want to see normal operating temperature within a specified time range, normally 12 minutes. So you want to at least run it for 15 to 20 minutes every week, if possible."

Datzkiw and Cousin emphasize that starting the vehicle for only a few seconds or minutes in the extreme cold, and not allowing it to reach normal operating temperature, will do more harm than good.

"That's almost worse in some cases, because the exhaust system will fill up with water," says Cousin. "You know how cars always steam like crazy when you first start them? That's condensation because of the reaction to hot and cold. If you just start and idle them your muffler system fills with water, and it doesn't go anywhere because you never get it up to operating temperature. In that case, you're better just to leave it alone."

Make sure the vehicle's fluids are in good shape before you leave. "Check the oil in advance, make sure it's fresh and clean. Make sure the coolant is good for a negative temperature," Datzkiw says.

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Filling the fuel tank is also advised. "If left empty, a situation can arise where the top of the tank will condense and moisture will form. Water is very bad in the gas tank. If the tank is full, you've got no room for moisture," Datzkiw says.

Finally, ensure the tire pressure is up to the manufacturer's recommendation, (this can be found on a sticker inside the door jam).

"What will happen after a car sits for a long period of time, and it's worse if the tires are a bit low – they will develop flat spots," says Datzkiw. "So there will be a thumping when you drive the car until the tires warm up and those flat spots become round again. That's why it's also important to move the car, so they can stop in a different spot every time."

If you have questions about driving or car maintenance, please contact our experts at

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