Do Cars Using E85 Start In The Cold?

Posted in: eFlexFuel Blog

Do Cars Using E85 Start In The Cold?

Are you switching to E85 fuel (or considering a switch to E85 fuel)? You may have some concerns about cold weather. For example, you may wonder if engines using E85 start in the cold. Ethanol is not quite as cold start friendly as gasoline, but it still starts in cold weather.

Why Ethanol Is Not Quite As Cold Start Friendly As Gasoline

Ethanol is an effective coolant and antifreeze agent. It helps keep the engine running cool. (It is also used to prevent the coolant from freezing in subzero temperatures.) Ethanol is an alcohol, it doesn’t freeze. This makes ethanol an excellent antifreeze agent for gasoline. Yet, it’s hard to ignite it in freezing temperatures.

With the presence of ethanol, the volatility (vapor pressure) of gasoline increases. For ethanol to warm up, it needs to vaporize. The increased volatility means it takes more energy for ethanol to vaporize. Cold temperatures make this harder. So the colder the weather, the more time and energy it takes for ethanol to vaporize. Ethanol takes more time than gasoline to vaporize. This is why a car with E85 doesn’t necessarily run or idle the best in cold weather until the engine is warmed up.

Why You Shouldn’t Worry About This

First off, if you live in a relatively warm climate, like most of California, this will never be a problem. Secondly, the flex fuel industry is well aware of this problem. That’s why flex fuel producers offer a winter blend for cold weather. Regular E85 contains up to 85% ethanol and 15% gasoline. Winter blends often have lower amounts of ethanol and you can also fill up with some gasoline to lower the ethanol content.

As long as you have some gasoline mixed with E85 in your vehicle, even in the dead of winter, you don’t have to worry about cold starts. Yet, there are a few ways to ensure smooth cold starts in the winter with flex fuel:

Ways To Ensure Smooth Cold Starts With Flex Fuel

Are you still worried about having difficulties starting up your engine with flex fuel in cold weather? There are a few things you can try:

  1. Start parking inside a garage, if you have access to one. Indoor garages are considerably warmer than the outdoors.
  2. Start using an engine block heater. An engine block heater is a small electric heater that usually mounts to the engine with magnets. It is powered by plugging into a wall outlet with and extension cord. Its job is to heat the engine up before a cold start. It gives your engine a "head start" when warming up.
  3. Even if you're using a winter flex fuel blend, you can add a little bit of gasoline to your fuel tank. If you add 10% or more of gasoline, it will considerably lower the ethanol content even more.
  4. Make sure your engine is well maintained. It's a good idea to check your spark plugs and ignition components (and replace them if needed) right before winter hits.
  5. Install eFlexPlus or eFlexPro. These are first-ever flex fuel converter kits that come with an adjustable cold start feature. The feature is accessible from the eFlexApp smartphone application or eFlexTuner Windows software. With this feature, you can configure the cold start specifically for your vehicle. eFlexFuel kits were developed in Finland (and it's not exactly balmy there in the winter). So it's safe to say that we know quite a bit about starting up a flex fuel powered engine in freezing temperatures.
5 months ago