How to Prepare Your Car for Long-Term Storageby Contributor
Here's what you need to do to make sure your car will start and run smoothly after being stored.
Choose a garage or other storage facility that's dry. Damp air will cause rust over a long period of time.
Fill the gas tank and add a fuel-stabilizing additive to prevent the gas from oxidizing and deteriorating. An empty or low gas tank will rust internally as moisture may accumulate inside the tank.
Relieve the weight from the tires by putting the car up on jack stands (available for about $15 a pair - you'll need two pairs). Check with the owner's manual and/or your mechanic about the safest place to place the jack stands.
Wash and wax the car well to prevent corrosion.
Disconnect the battery (although it will probably need to be replaced later, anyway) so the alarm doesn't go off. For shorter term storage (when you're not in the area) you can ask a friend to start up the car every few weeks and let it run for five or 10 minutes (don't run a car in a garage without proper ventilation - carbon monoxide can kill).
Cover your car with a good quality car cover or tarp.