What’s the best winter fuel additive in 2023?
The market is littered with products claiming to be the “best fuel additive for cold weather”. With dozens of variations being sold, it begs the question which winter fuel additive works the best? You want to save money where you can so doing the research is important.
You can pick up STP fuel additives at any gas station on Earth but are these cheaper quality fuel supplements worth buying? Even at a fuel station, the price for STP products is usually reasonable. When the temperature dips below freezing though will these cheap fuel additives protect your vehicle from a fuel line freeze up no-start condition?
In this post, we’re going to look at the benefits of a fuel additive in the winter, how things like “dry gas” made by Iso-Heet help protect your vehicle and how much you can expect to spend on a good, quality fuel additive to put in the tank this winter. Finally, we’re going to weigh the benefits of each fuel additive and decide which one is best in cold weather.
What are the benefits of fuel additives in cold weather?
If there wasn’t a benefit, no one would put a fuel additive in the tank. What exactly is the benefit of fuel supplements like K100 when winter hits and the cold weather arrives?
- Fuel additives like the ones Iso-Heet, K100 and STP market are easy to use. Most products are simply poured into a full tank of fuel and driven normally.
- The main advantage gained by using a fuel additive in the winter is prevention of frozen moisture causing a no start or damage to the fuel system.
- Even fuel supplements made to prevent freeze ups often use detergents and lubricants to help maintain a healthy fuel system year round.
- In diesel systems, wax crystals will form together under cold conditions and cause a no-start. Good fuel additives use technology to prevent these costly freeze ups.
- Easier starts-especially with Diesel engines- are an important benefit of winter fuel additives. Nothing like a freeze up followed by a bad starter from cranking the engine repeatedly.
- No costly tow or auto repair bills when the winter cold causes the moisture in your tank to freeze.
Its no secret to anyone living in the Northern Hemisphere that fuel line freeze up is one of the most common issues with fuel powered vehicles. This applies to gasoline and diesel although diesel is more prone to the issue if preventative measures are not taken.
How do fuel additives prevent freeze ups and improve performance?
Learning how winter fuel additives work is an important part of choosing which one to buy. Each product claims specific benefits to the fuel system, but do they work? Also, how do they improve the performance of your cars engine. Performance should be a priority all year around but it is absolutely pertinent in the winter time.
One of the oldest and most widely used winter fuel treatments is made by ISO-Heet and marketed as fuel line antifreeze. Some variants also add “fuel injector cleaner” on the label. Those products use a mixture of chemicals to prevent frozen gas lines and also clean, lubricate the injectors and entirety of the system.
Isopropanol or Isopropyl Alcohol are a main ingredient in fuel line antifreeze.
Iso-Heet’s Gas Line Antifreeze uses isopropanol as it’s main ingredient and method of preventing and fixing frozen fuel lines. Also known as isopropyl alcohol, isopropanol has a freezing point of -128.2 degrees Fahrenheit. It’s this extremely low freezing point that makes isopropyl alcohol a common additive in fuel line and other “antifreeze” products.
Gasoline in contrast can freeze between -40 and -200 degrees Fahrenheit. Diesel fuel is far more concerning as the wax inside of it starts to freeze at 32 degrees Fahrenheit. This is called the gel-point and it’s good to be familiar with if you own a diesel. For this reason, it is important to always run a diesel fuel additive in the winter time.
What about performance?
Fuel additives that improve performance do so by adding lubrication and detergents. Like any mechanical system, a cars fuel system has moving parts. Injectors open and close, fuel gets pumped from the tank, etc.
By using chemicals formulated to keep the fuel system clean and lubricate any moving parts, fuel additives can improve performance. Some fuel additives also use “octane boosters”, which can improve performance in the same way using higher octane gasoline does.
Using fuel additives is especially important in GDI engines where carbon build up is a major issue. It’s also recommended to use higher octane fuel in GDI engines, but an additive won’t hurt. They even make GDI specially formulated fuel additives.
How much do winter gas/diesel additives cost?
When deciding which product to use, it’s important to consider the cost of each winter fuel additive. We already discussed the benefits, but for a product you might use 20-30 times a year depending where you live and how often you drive it’s important to get the best bang for your buck.
As with everything else, fuel line antifreeze products and diesel anti-gel solutions range in price depending on quality, brand and added benefits.
Here are a few winter additive recommendations based on different scenarios.
1). Gasoline engine- High mileage/year.
If you’re going to be filling up regularly in the winter time with a gasoline engine I would recommend a product like ISO-Heet Gas Line Antifreeze. It’s a reasonably priced, trusted winter time fuel additive and you can buy a case on Amazon for around $50 that should last all winter.
If you’re buying in the store, this is the yellow bottle of what everyone refers to as “dry gas” because it also “removes” water from gasoline. If keeping the fuel system clean and performing at its best while also preventing freeze ups is your goal- reach for the red bottle of the same brand.
The red bottle of ISO-Heet is around $80 for a 24 count but still much less than the cost of repairs if your fuel system gets contaminated with water or components like the fuel pump or injectors fail due to lack of maintenance.
2.) Diesel Engine- Mileage does not matter.
As I mentioned, the gel-point or temperature at which Diesel fuel begins to gel is around 32 degrees Fahrenheit. In New York, it starts to get that cold in September some years. It would not be hard to cause a disaster if you don’t take steps to avoid a Diesel gel-up situation.
One year when I worked at Casella’s, we got a batch of Diesel out of Albany that was not properly winter treated. On the first day below freezing, 60 pieces of equipment sat in the yard because the fuel had gelled and none of them would start. Following that incident, we started using K100 Diesel Treatment and never had an issue again with trucks that wouldn’t start in the winter.
You can buy K100 for Gasoline Engines on Amazon also.
We obviously bought our Diesel additive in bulk, but you can buy K100 in an eight ounce bottle for around ten dollars on Amazon. It’s well worth the money. Power Service Diesel is the other popular choice for winter diesel additives and it seems to be equally effective. There also a range of Power Service Diesel additives to choose from, including Diesel 9-1-1 which we will touch on more.
3.) Your fuel lines are already frozen.
Diesel
It’s inevitable that some of you are reading this post because the fuel lines in your car or truck have already frozen. Thankfully, you are not alone and frozen fuel lines or gelled up diesel systems are fairly common in the winter. Where there is a market, there will always be a product.
I mentioned Diesel 9-1-1 above as part of the Power Service line of diesel fuel additives. This winter additive is for those cases where water has already contaminated the fuel system causing a gel up situation. It’s formulation is meant to restore the flow of Diesel after the wax has frozen and gelled up causing a no-start condition.
Diesel 9-1-1 is not one of the additives that you put in every tank. It’s the fuel additive you keep behind the seat of the truck. When the situation arises, you will wish you had a bottle to unthaw the “frozen” diesel fuel.
Gasoline
When the gas lines freeze in your gasoline engine the best way to thaw them is obviously to warm the vehicle. It’s likely this won’t be practical in the winter though. Therefore you will need a fuel additive designed to unfreeze your fuel lines.
The yellow bottle of Iso-Heet referenced above is the best option for this purpose but simply adding the dry gas to your tank isn’t likely to fix the problem. If the frozen gas is in the lines, pouring Iso-Heet in the tank will not suffice.
In order to unthaw the gas lines in your car, my advice is to get at least five gallons of fuel (more if possible) and mix the fuel additive in that before putting it in the tank. Let the mixture sit for an hour. Next, crank the engine once or twice every 5-10 minutes as to allow some of the dry gas to get in the lines.
If this method fails after several attempts, you may be stuck calling a tow truck and spending hundreds or more to fix the frozen fuel system.
Preventing fuel lines from freezing using additives is the best approach.
Prevention is ultimately the best way to keep your fuel lines from freezing and costing money. The only proven way to prevent those frozen lines is to use a winter fuel additive all season!
