You can safely leave a car in a garage for several months, but proper preparation is essential to prevent damage. The primary enemies of a stationary vehicle are the battery discharging, fuel degrading, tires developing flat spots, and fluids breaking down. Without any preparation, you might start experiencing issues like a dead battery within four to six weeks. However, with a few key steps, a modern car can be stored for six months to a year with minimal problems.
The single most important factor is the battery. A car's battery will slowly discharge due to the small electrical draws from the vehicle's computer and alarm system. To avoid a dead battery that can be damaged by a deep discharge, using a battery maintainer (or trickle charger) is highly recommended. This device plugs into a wall outlet and keeps the battery at an optimal charge level indefinitely.
Fuel stability is another critical concern. Standard gasoline can begin to degrade and form varnish and gums in the fuel system in as little as 30 days. Before storage, fill the tank with fresh fuel and add a fuel stabilizer. This additive prevents degradation and protects the fuel injectors and pump. Running the engine for a few minutes after adding the stabilizer ensures it circulates throughout the system.
To prevent tire flat-spotting, where the weight of the car flattens the section of tire touching the ground, inflate your tires to the maximum pressure listed on the tire's sidewall. For very long-term storage (over six months), placing the car on jack stands to take the weight off the tires is the best practice.
Here’s a quick reference table for key preparation steps:
| Preparation Step | Action Required | Benefit |
|---|
| Battery Maintenance | Disconnect negative terminal or use a battery maintainer. | Prevents complete discharge and battery damage. |
| Fuel System | Fill tank + add fuel stabilizer; drive for 10-15 mins. | Prevents fuel degradation and clogged injectors. |
| Tire Care | Inflate to max sidewall pressure (or use jack stands). | Prevents permanent flat-spotting of tires. |
| Fluid Check | Change oil and coolant if near due; top off other fluids. | Ensures clean fluids protect internal components. |
| Cleanliness | Give car a thorough wash and wax; clean interior. | Protects paint and prevents mold/mildew. |
| Pest Deterrence | Place mothballs or peppermint oil sachets in cabin/engine bay. | Discourages rodents from nesting and chewing wires. |
Finally, give the car a good wash and wax to protect the paint, and clean the interior to prevent mold. If you're storing a car for over a year, more extensive preparation, like changing all fluids beforehand, is advisable. The key is to think about protecting the car from inactivity itself.
