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How to Start a Car in Cold Weather

Even if you’ve never been to the island, there’s one thing that everyone knows: things can get pretty icy. And no matter how much snow you shovel, mechanical things such as cars will always give you a little bit of trouble on those freezing mornings. Unless, of course, you know how to start a car in cold weather.


And if you don’t, don’t worry. This article will serve as a step-by-step guide to help you become a cold-weather wizard when it comes to your pride and joy (or the rental from the agency).


How to start car in cold weather

Reasons Why Your Car Might Not Start in Cold Weather


We often get asked the questions “why won’t my car start in the cold?” and “how to jump-start a car in cold weather” when it comes to driving in Iceland. These are all very normal questions for visitors who come from warmer parts of the world. Even for those who tend to make use of public transport systems rather than driving their own vehicle.


There can be many reasons why a car is struggling to start when it’s cold. We’ll be going through a few of these before diving into tips on what to do if a car won’t start in the cold:


Your engine oil has essentially turned to syrup


It’s important to remember that your engine oil needs to run through small spaces of roughly 0.05 mm. These small spaces are necessary because the engine has so many components that need to move at very high speeds.


So, the moment the cold turns your engine oil into a thick sludge, it causes too much friction for these fast-moving components. That can easily give cause for your car not to start.


Your battery’s performance might be compromised


Battery current decreases along with the temperature. This is because the cold impacts the chemical reaction between the plates and the battery’s electrolyte. And if the battery doesn’t have enough power, your car doesn’t have enough power.


In severe cases, it’s not even enough power for your car to start. When this is the case, your car won't start in the cold, and you’ll hear a clicking noise.


New battery car won't start in cold

There’s moisture in the fuel line


Okay, bear with us, ‘cause this one can be a bit technical for those of us without much mechanical knowledge. The fuel system in a car is much more complicated than just putting and gas to make it run. There are things like a fuel injector, a fuel pump, a fuel pump relay, and multiple fuel lines working between these parts.


Sometimes, the fuel line itself can freeze which causes a blockage or lower fuel pressure, which could be the reason why your car won’t start in the cold. But the reason why the fuel line can freeze in the first place is that it got moisture inside it. And the reason why it got moisture inside it is also because of the cold.


When the fuel tank level drops, there’s more space for condensation. It is this condensation that ends up moving from the gas tank to the fuel line, where it freezes once the temperature drops.


You’re using the wrong oil


Remember the engine oil that turns to thick sludge in the cold? Well, certain oils are already on the thicker side from the get-go. That is why it’s advised that drivers living in colder regions get thinner oil from the start. Double-check which oil to use with your local rental agent or vehicle repair shop.


You’re dealing with the curse of the carburettor


Older cars (manufactured at least 30 years ago) would still have a carburettor. A carburettor mixes fuel with air to make it combustible in the engine block. But the carburettor has tiny nozzles that are highly susceptible to colder temperatures. They can easily get clogged by ice, which also makes it hard for a car to start.


Start car in extreme cold

A Step-by-step Guide on How to Start a Car in Cold Weather


If you’re ever left out in the cold and you have problems starting the car, try the following steps:

  1. Make sure everything’s switched off before turning on the car. That means no heater, no headlights, no radio, etc. These will all merely take more power away from the engine.

  2. Turn the key. If the ignition starts – wonderful! If not, crank it again and for an extra couple of seconds. Just make sure not to crank it for more than 10 seconds, as this can cause the starter motor to overheat.

  3. Still not starting? Wait a couple of minutes and try again.

  4. If your car still has a carburettor, try starter fluid.

  5. If the battery is completely dead, you can try to jump-start the car.

  6. All else failed? Then it’s time to call for some roadside assistance.

Some General Tips on How to Start a Car in Cold Weather


If you ever experience any of the above-mentioned problems, these are a few tips and tricks to try on how to start a car in cold weather:

  • Double-check that all battery cables and terminals are connected properly. A minor disconnect can happen and cause trouble starting the engine whether you’re in cold weather or not.

  • Ensure that you have sufficient engine oil in the car. If not, fill it up.

  • Dip the clutch when switching on the ignition. This will disengage the gearbox and allow for the battery only to have to power the starter motor.


How to jump start a car in cold weather

Tips on How to Prevent a Car from Struggling to Start When Cold in Future


They say prevention is better than cure, so here are a few tips to avoid a car that won’t start in the cold:

  • Get everything checked before the Iceland winter season comes, especially the battery and the engine oil.

  • Keep your car warm. This can be done by keeping it parked in a closed garage, placing canvas over it, or keeping it underneath a carport.

  • If it goes below -15 degrees Celsius, it’ll be better if you get an engine block heater.

  • Ensure that your coolant is topped up.

  • Always keep your car insurance up to date, especially if it includes roadside assistance.

Frequently Asked Questions Regarding How to Start a Car in the Cold


Didn’t find the answer you’re looking for yet? Then take a look at some of the frequently asked questions below:


Is a diesel car that won’t start in the cold the same as a petrol car that won’t start in the cold?


The short answer is, yes. Diesel cars (usually 4x4 vehicles in Iceland) require much higher temperatures to fire the fuel. So, even though most cars will struggle to start in the cold, a diesel car will struggle even more.


I have a brand-new battery, but my car still won’t start in the cold. What could be wrong?


As we’ve mentioned, it’s not always the battery that’s causing issues. Go through all our reasons why a car won’t start in the cold and eliminate the possibilities one by one.


Cold start car problems

Even though it’s not a new battery, my car won't start in the cold and it's not the battery causing the problems. What should I look out for next?


As mentioned in our previous FAQ, start going through the options and tick them off one by one.


What if my push-button car won't start in the cold?


The start button is merely a replacement for a key in an ignition, so generally, the same rules apply with just one exception. You need to add the possibility of there being a problem with the key fob if the car won't start.


My car is shaking on cold start. What could the problem be?


There can be a myriad of reasons why your car is shaking. These include:

  • Your fuel tank is low.

  • The fuel you’re using is of lower quality.

  • Your car battery isn’t properly charged.

  • The fuel pump is not pumping the fuel properly.

  • Something’s wrong with the spark plugs.

  • Something’s wrong with the spark plug wires.

  • The timing belt or timing chain is worn out.

  • Something’s wrong with the oxygen sensor.

  • The engine mounts are faulty.

  • Your engine has dirty or failing injectors.

  • Something’s wrong with your idle speed sensor.

How long does it take to start a car in cold weather?


That depends on a variety of things such as the car, the temperature, the problem, etc. It can take you just the first two steps of our to-do list before it starts up, or you can end up having to call for assistance.


Start a car in winter

How often should I start a car in cold weather?


This is an incredibly important question. Remember how we mentioned that the starter can actually overheat when making too many attempts for too long? So stick to the general rule of thumb of trying for no more than 10 seconds at a time and waiting at least a minute or two between each attempt.


Basically an Expert


If you’ve read this article thoroughly, we’ve not only answered the question “will my car start in extreme cold?”. We've also given you all the information you’ll need to get your “baby” back on the road. But before you go, make sure to check our top tips for driving in snow to make sure nothing will stop you once you hit the road.


If you are planning on visiting the island soon and don’t have your own transport yet, simply rent a car in Iceland. You can rest assured that your rental agency will be more than helpful when it comes to how to start a car in cold weather and any extras you may need in Iceland. Freezing weather in Iceland never means a frosty reception.

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