Symptoms
- Car will be stored for weeks or months (deployment, seasonal home, extended travel)
- Not sure what to do before leaving a car unused
- Previous storage led to a dead battery or flat-spotted tires
Likely causes
- CommonFuel degrading over timeGasoline can start to break down and gum up the fuel system after a month or more, especially with ethanol blends.
- CommonBattery self-dischargeBatteries slowly lose charge even when the car is off, and can end up too weak to start after weeks of sitting.
- PossibleTire flat-spottingTires can develop flat spots from sitting in one position for a long time, especially if underinflated.
What to do
- Fill the gas tank fully and add a fuel stabilizer to slow fuel degradation.
- Change the oil before storage if it's due soon, since contaminants in old oil can sit and cause corrosion over time.
- Inflate tires to the upper end of the recommended range (check your door jamb sticker) to help resist flat-spotting.
- Either disconnect the negative battery terminal or, better, connect a battery maintainer/trickle charger if power is available.
- Wash and wax the car, and consider a breathable car cover if stored outside, to protect the paint over a long period.
- If possible, have someone start and briefly drive the car every few weeks, or at least run the engine for 10–15 minutes.
Tools and parts
- Battery maintainer (optional)
- Car cover (optional)
Fuel stabilizerSearch: “fuel stabilizer for gasoline”
When to call a pro
No professional needed for typical storage prep; if the car will sit for more than 6 months, consider having a shop advise on additional steps for your specific vehicle.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.