Can you stand the heat? What you should know about Vapor Lock!

Can you stand the heat? What you should know about Vapor Lock!

With the temperatures rising in these summer months coming up it’s time to talk about vapor lock. If you’re fortunate enough to have never dealt with vapor lock, you might be wondering what it is. A vapor lock is when the fuel in your vehicle vaporizes before it can reach the engine. This can cause a variety of issues while driving when it happens.

How does vapor lock occur: When the fuel in your vehicle reaches a certain level of heat it starts to boil. This happens in either the fuel line or the carburetor. Excessive heat around the fuel lines and components causes the fuel in your vehicle to boil. Once the fuel starts to boil it causes it to vaporize which then leads to air bubbles. These air bubbles stop the natural flow of fuel going from the fuel tank to the engine.

What is my fuel boiling point: The boiling point for fuel can vary because the types of fuel we use vary. There are different blends available to us for our vehicles and some blends will reach a boiling point before others. One of the reasons vapor lock is more prominent today than it was in the past is due to the addition of ethanol to our gasoline. Ethanol has a lower boiling point than pure gasoline. In addition to having fuel blends, unfortunately, with older vehicles, the motors aren’t built to work as well with these fuel blends. So, you might see vapor lock happening more often in older vehicles, but it happens with new vehicles as well. Why do we keep adding ethanol to our gas blends if it has a lower boiling point and causes issues such as vapor lock? Ethanol helps boost the performance of our vehicle engines by adding more octane to unleaded gas. It also can burn almost completely which helps prevent harmful emissions from going out of our tailpipe and into the atmosphere.

What issues does vapor lock cause: There are a few things that can happen when your vehicle experiences vapor lock.

1. Stalling– where the engine stops and the vehicle will not go.
2. Hard Starting– when the vehicle is having a hard time getting started.
3. Misfiring– when your vehicle is idling the RPMs will drop and then go back up to normal giving a feeling of lost power or like the vehicle is having difficulty.
4. Poor Acceleration– where your vehicle has a hard time accelerating.
5. Rough Running– when your vehicle is performing at a lesser quality than usual, possibly even sounding “rough”.
6. Hesitation– where there is a lack of power behind the vehicle when you accelerate.

Prevention: You should always check with a professional about how to address issues with your specific vehicle, we here at Busbee’s would like to share some ideas with you!

1. Nylon Fuel Hose VS Steel line-If you have the option, to get a nylon fuel hose rather than a steel line. Steel lines take in a lot of heat which heats the line and the gasoline going through it much more quickly. With a nylon fuel hose, it will take in a lot less heat and is compatible with most fuel types.
2. Heat Shield VS Heat Sleeve– Another thing you can do is add a heat shield to your vehicle so the engine is more isolated and takes in less heat. This will help with vapor lock issues and any other issues that can occur when the engine gets overheated. You can also get a heat sleeve which is meant to keep heat away from the lower parts of the vehicle such as the transmission tunnels.

We can’t stop the summer months from heating up, but we can do our best to stop vapor lock! With the knowledge of what it is, what issues it causes, and how to prevent it we can try to take vapor lock and make it a thing of the past. If you have any questions about vapor lock or want to know more give Busbee’s a call at 803-580-6514, or visit our website


Please enable JavaScript in your browser to complete this form.


Scroll to Top