Whether you’re heading abroad for work, putting a classic away for winter, or simply won’t need the car for a few months, leaving it parked up without preparation is a recipe for problems.
Flat batteries, seized brakes, stale fuel and cracked tyres are all common outcomes when a car sits idle without the right steps taken beforehand. Let’s take a closer look at what you’ll need to do before handing over the keys to your garage or storage facility.
Give the Fuel System Some Attention
Petrol starts to degrade after about 30 days. Over several months, it can leave gummy deposits in your fuel lines and injectors that are expensive to sort out. If you’re storing the car for longer than a month, add a fuel stabiliser to a full tank before you park up. A full tank also reduces the amount of air inside, which limits condensation and the risk of rust forming in the tank.
Run the engine for 10 to 15 minutes after adding the stabiliser. That will circulate it through the entire fuel system and protect components you can’t easily reach yourself.
Battery Conditioning and Disconnect
A car battery will slowly drain even when the engine’s off. Dashboard clocks, alarm systems and onboard computers all draw small amounts of power. After a few weeks, you could come back to a completely dead battery.
You’ve got two options here. The simplest is to disconnect the negative terminal, which stops the drain entirely. The better option, especially for longer storage, is to connect a battery conditioner or trickle charger. These devices monitor the charge level and top it up automatically, keeping the battery healthy without overcharging it. Most decent ones cost under £40 and will pay for themselves by extending your battery’s life.
Tyre Pressure and Flat Spot Prevention
Tyres lose pressure gradually, even when the car isn’t moving. When a car sits on underinflated tyres for weeks, the rubber develops flat spots where it meets the ground. In mild cases, you’ll feel a vibration when you first drive again. In severe cases, the tyres will need replacing.
Inflate your tyres to the upper end of the manufacturer’s recommended range before storage. If you’re leaving the car for more than three months, consider placing it on axle stands to take the weight off the tyres completely. That’s the most reliable way to avoid flat spots.
Top Up All Fluids and Change the Oil
Old engine oil contains contaminants and acids that can corrode internal engine parts when the car sits still. A fresh oil change before storage will protect the engine far better than leaving old oil in the sump.
While you’re at it, top up the coolant, brake fluid, and windscreen washer. Low coolant can lead to corrosion in the cooling system, and brake fluid absorbs moisture over time, which affects performance when you eventually get back on the road.
Protect the Paintwork and Interior
A good wash and a coat of wax will protect your paintwork from dust, moisture and minor surface damage during storage. Pay attention to the underside too, particularly if you’ve been driving on salted Welsh roads over winter. Road salt left on metal components will accelerate corrosion.
Inside, give the cabin a thorough clean and place moisture-absorbing bags or a small dehumidifier on the floor. This will prevent mould and musty smells from developing. Leave a window cracked very slightly if you’re storing in a ventilated space, but keep them shut tight in uncontrolled environments.
Your Car Still Needs Regular Attention in Storage
This is where many owners slip up. They assume that once the car’s tucked away, the job’s done. But a stored car still needs periodic maintenance to stay in good condition. Ideally, someone should start the engine every two to four weeks and let it reach full operating temperature. This circulates the oil, charges the battery (if no conditioner is fitted), and prevents seals from drying out.
Brake and clutch pedals should be pressed regularly too. Brake discs can develop surface rust in as little as a week, and clutch plates can stick to the flywheel over time. Rotating the tyres or at least moving the car a short distance will also help prevent flat spots.
For many people, keeping up with all of this regularly just isn’t realistic, especially if the car is stored away from home. That’s one reason why quality facilities offering professional car storage in the UK typically include scheduled engine running, fluid checks, and condition monitoring as part of their service. It takes the ongoing responsibility off your hands.
A Quick Pre-Storage Checklist
Before you lock up and walk away, run through these final steps:
- Fill the fuel tank and add stabiliser
- Change the oil and top up all fluids
- Inflate tyres to the upper recommended pressure
- Connect a battery conditioner or disconnect the negative terminal
- Wash, wax, and clean the interior thoroughly
- Place moisture absorbers inside the cabin
- Release the handbrake (use a wheel chock or leave in gear instead)
That last point catches people out. Leaving the handbrake on for months can cause the brake pads to bond to the discs. A simple wheel chock does the same job without the risk.
Don’t Just Park It and Forget It
Preparing a car for storage takes a couple of hours at most, but it’ll save you from a long list of problems when you come back to it. The fuel, battery and tyre steps are the most critical, and they’re all things you can handle yourself with basic tools and supplies.
Where it gets harder is the ongoing maintenance during storage. If you can’t commit to regular check-ins, it’s best to hand that part over to someone who will. Your car will thank you for it when it’s time to turn the key again.
