Fuel Frequently Asked Questions
Exxon-Mobil Fuel FAQs
Why should I use Exxon or Mobil branded fuel every time I fill up?
When you purchase gasoline at an Exxon- or Mobil-branded, you’re fueling with advanced Synergy gasoline. Engineered with 7 key ingredients to help you get better gas mileage,** Synergy gasolines provide lower emissions and improved engine responsiveness** and are designed to provide corrosion protection and improved performance compared with gasolines meeting minimum government detergency standards. In addition, Exxon and Mobil Synergy™ gasoline contains significantly higher detergent levels than EPA requirements and has passed a series of deposit control performance tests, resulting in it being certified TOP TIER®.
Does gasoline really need detergents?
Yes! Detergents are added to gasoline to help clean vital engine parts, including fuel injectors and intake valves. In 1995 the EPA has mandated that all gasoline marketed in the United States contain detergents. Many of our fuels contain significantly more than the minimum quantities required. In fact, Synergy gasolines from Exxon-Mobil contain two detergents, one that’s a lot like a household detergent, helping to remove any harmful deposit buildup and one that targets the toughest gunk.
What is unleaded vs. leaded gasoline?
If you filled your tank prior to the 1990’s, you might remember that there were two choices of gasoline: “regular” and “unleaded.” At the time, “regular” gasoline contained tetraethyl lead, which served as an octane booster in fuel. All vehicles manufactured after 1975 are built with catalytic converters and require unleaded gasoline. Catalytic converters help convert pollutants in exhaust to less toxic gasses such as carbon dioxide, nitrogen, and water vapor. Due to environmental concerns, leaded gasoline was phased out in the 1990’s and can no longer be sold at any gas station in the United States. Today, “regular gas” no longer refers to gasoline with lead content, but rather to a certain grade of unleaded gasoline.
How is gasoline performance determined?
The performance of gasoline is determined by multiple factors, including its antiknock quality (also known as octane rating), its volatility, and its detergency. Check your owner’s manual to see what octane rating is right for your vehicle.
What does antiknock mean?
Antiknock, also known as octane rating, is a measure of the gasoline’s ability to resist knocking or pinging during combustion. Since it is gasoline vapor rather than liquid fuel that ignites, the air-to-fuel mixture must be correct for smooth combustion. The higher the octane rating, the greater the engine’s resistance to knock. Some of the problems associated with knock are overheating of critical engine parts – namely valves, pistons and spark plugs. To minimize the effects of knocking, modern engines are equipped with knock sensors, which temporarily delay the spark timing in the piston’s compression cycle. While this prevents audible knocking, delaying the ignition spark also sacrifices engine efficiency.
What does volatility mean?
Volatility refers to a series of characteristics that measure a fuel’s tendency to vaporize at a given temperature. Since gasoline must vaporize before mixing and burning with air, formulating fuel with the correct volatility is critical for achieving good drivability. High volatility gasoline vaporizes more readily than low volatility fuel and is frequently blended during the winter season to ensure easy cold startup and smooth warm up. In hot weather, gasoline that is too volatile can cause vapor lock and other hot fuel handling problems. Exxon and Mobil gasoline is carefully formulated on a seasonal and geographic basis to provide the correct vaporization characteristics for proper vehicle operation.
What does detergency mean?
Detergency is the performance characteristic of a gasoline that refers to its ability to clean and protect the fuel delivery system, including the carburetor or fuel injectors, and intake valves. A gasoline detergent is fundamentally like a household detergent. It is a molecule that affixes itself to dirt particles. As gasoline passes through a car’s engine, the molecule helps clean away dirt particles and helps to prevent any harmful deposit build-up.
What is Synergy Diesel Efficient fuel, and how does it differ from regular diesel?
Synergy Diesel Efficient diesel fuel was developed in the same laboratories as our racing fuels. It has been engineered to improve fuel economy (2% on average*), boost engine performance, reduce maintenance and provide cleaner emissions.
*Fuel economy improvement is based on Synergy Diesel Efficient compared to unbranded diesel fuel without detergent additive. Vehicle testing showed an average fuel economy improvement of 2 percent. Actual benefits will vary depending on factors such as vehicle/engine type, driving style and diesel fuel previously used.
Is Synergy Diesel Efficient fuel only for commercial vehicles?
Synergy Diesel Efficient diesel fuel is designed to provide benefits in all types of applications, whether in a personal vehicle or a fleet of trucks. It is formulated for use in any vehicle fueled by diesel.
How will Synergy Diesel Efficient fuel benefit my vehicle?
Tested in independent laboratories and in multiple real-world applications, Synergy Diesel Efficient fuel showed a 2 percent quantifiable fuel economy benefit.* It has been found to improve engine performance, clean fuel injectors, help remove deposits and enhance corrosion protection.
*Fuel economy improvement is based on Synergy Diesel Efficient compared to unbranded diesel fuel without detergent additive. Vehicle testing showed an average fuel economy improvement of 2 percent. Actual benefits will vary depending on factors such as vehicle/engine type, driving style and diesel fuel previously used.
Where can I purchase Synergy Diesel Efficient diesel fuel?
Throughout 2018 and beyond, Synergy Diesel Efficient fuel will be offered throughout the United States and Canada.
When purchasing Synergy Diesel Efficient fuel, am I able to spend or earn loyalty points on a purchase?
Yes. As part of the Synergy™ fuels family, our loyalty program works the same way for Synergy Diesel Efficient fuel as it does with Synergy™ gasoline.
Where can I go to learn more about Synergy Diesel Efficient diesel fuel?
Visit the following pages on the Exxon-Mobil website to learn more about our Synergy Diesel Efficient for commercial fleets and Synergy Diesel Efficient for passenger vehicles.
Will gasoline with ethanol affect my vehicle’s fuel efficiency?
Ethanol contains less energy than gasoline per gallon of fuel, but any changes in the fuel economy performance of your vehicle are expected to be minimal.
If I have water in my vehicle’s fuel system can I use ethanol-blended fuel?
Water in your vehicle’s fuel system may cause problems regardless of whether ethanol is present or not. A number of products are available to remove water from your fuel system. You should consult your mechanic for a recommendation.
Will my vehicle require additional maintenance?
Regular vehicle maintenance is always recommended, regardless of fuel type. Gasoline containing up to 10% ethanol is suitable for use in most vehicles and will not require additional maintenance.
Is there a situation where my vehicle’s octane needs would differ from the level recommended in my owner’s manual?
In general, the octane needs of a vehicle align with the manufacturer’s recommendation. However, a small percentage of vehicles may require higher octane fuel under certain conditions. Extremely hot weather, changes in altitude, or exceptionally hard driving conditions, such as towing heavy loads, may cause knocking. Additionally, knocking may be the result of slight variations in engine construction variability or unusual engine deposit build-up. Many modern vehicles are equipped with electronic knock sensors that detect and eliminate light knocking before you hear it.
Why do gasoline prices fluctuate?
The major factor in fluctuating gasoline prices is the price of crude oil, which is continually impacted by supply and demand. Crude oil impacts the price of gasoline just like other commodities such as corn, coffee and cotton, impact the price of goods. For example, a shortage of corn crops could cause the price of some foods to increase.
Why do gasoline prices differ between companies?
Even though all oil companies sell gasoline products, those products are not identical. Different manufacturers use different techniques and unique formulas in the refining process that may impact prices. As well, where and how a gas company sources their crude oil will impact prices at the pump.
What are some ways I can save at the pump?
We recognize that saving money on gas is important to every driver. That’s why we have put together a comprehensive list of tips and advice to help you improve your fuel economy – from what to look for when purchasing a vehicle to changes you can make to your driving habits.
Things to consider when looking for a fuel-efficient vehicle
- Think small – generally, the smaller and lighter the vehicle, the more fuel efficient it will be
- If you want a sedan or SUV, look for fuel-efficient technology such as a smaller, turbocharged engine with electric accessories, idle-stop, a multi-speed or continuously variable transmission, or a hybrid drive system
- Go for the highest MPGs – quite simply, the more miles your car can travel on each gallon of gas, the more money you’ll save
Car maintenance
Adjust your tire pressure and increase efficiency by up to 3%.†
Driving habits
Turn your AC off and save 1¢–2¢/min.†
Smart choices
Take the bus during the week and save the SUV for the weekend.
Tips to help you on your journey
We’ve put together a few tips, tricks and short cuts to help make getting where you need to go just a little bit easier.
Tips to help you stay safe around fuel
At all our gas stations, customer safety is of the utmost importance, and we adhere to strict safety practices to help keep customers safe at all times. But please remember, gasoline and diesel fuels are flammable, and therefore they can be dangerous, so always use caution. Never smoke anywhere near where fuel is handled, especially at the pump.
Source: “Tips for Safe Storage and Disposal of Gasoline.” Tips for Safe Storage and Disposal of Gasoline. American Petroleum Institute (API), n.d. Web. 06 Apr. 2014. ††Source: “Chemical splash in the eye: First aid” Mayo Clinic, 30 Jan 2015.
BP Fuel FAQs
What is Invigorate®?
Invigorate® is BP’s exclusive proprietary detergent additive found in all three grades of BP gasoline with Invigorate®–Regular, Silver (midgrade), and Amoco Ultimate® (premium). Fuel additives are good! In fact, the US government requires a minimum amount of deposit-control additive to be present in all US fuels – but all grades of BP gasoline with Invigorate® go beyond these minimum standards in an effort to provide additional benefits to drivers who use our fuel.
What does Invigorate® do?
An improved version of BP gasoline with Invigorate® was introduced in April 2016, and we’re proud to say this version is our best fuel ever–with versatility for both conventional port fuel injector engine technology, and emerging direct injection engine technology. It has 10 times better protection against intake valve deposits than ordinary, minimum-detergency fuels. Keeping intake valves clean is important because dirty deposits from ordinary fuels that form in engines can lead to a variety of problems–hesitation, rough starts, loss in fuel economy, and increased emissions to name a few.
BP gasoline with Invigorate® not only helps prevent deposits from forming in the first place, but can even help clean deposits left by minimum detergency fuels –giving drivers more miles with every tank¹.

BP gasoline with Invigorate®
Additionally, BP gasoline with Invigorate® protects against sludge which can build up over time in your engine’s motor oil system, preventing oil flow to critical engine parts and can result in catastrophic engine failure².
¹Ordinary Fuel refers to minimum detergency gasoline. Dirt refers to deposits on critical engine parts. Requires continuous use over 5000 miles. Restores an average of 3 – 5 miles per tank that had been lost due to deposits. Based on fleet testing representative of the U.S. car population. Fuel economy can be affected by many factors. Benefits may be more significant in older model vehicles
²With continuous use. Based on driving style. Follow vehicle manufacturers’ recommendations for oil changes.
How was Invigorate® developed?
BP gasoline with Invigorate® was developed with rigorous and extensive testing by fuel engineers, covering over 60 different industry approved test methods and thousands of hours in vehicles and engines. We tested our best ever fuel in conventional (port fuel injector) and emerging (direct injection) engine technology; in fleets of cars and trucks with engines big and small; and in engine test stands incorporating ASTM, industry standard and new, cutting edge test procedures.
Where can I find Invigorate®?
BP gasoline with Invigorate® can only be found at BP stations. Use our station finder to locate the BP nearest you.
What is Amoco Ultimate with Invigorate®, and how could it benefit my vehicle?
Amoco Ultimate® with Invigorate® is BP’s premium fuel.
Amoco Ultimate with Invigorate® is not a typical premium fuel whose only difference is octane number. Even cars whose manufacturer recommends regular fuel may see a benefit from using Amoco Ultimate with Invigorate®. This is because it contains our highest level of Invigorate® additive–meaning it can help clean a dirty engine even faster than BP Regular or BP Silver. Filling up with Amoco Ultimate with Invigorate® can also provide 20 times better protection against deposit formation when compared to ordinary fuel, helping to give engines the best protection that BP can offer.*
Many vehicles recommend or require premium fuel because their engines were designed to benefit from higher octane. For these vehicles, Amoco Ultimate® with Invigorate® delivers more power and quicker acceleration compared to regular grade gasoline. The difference can often be quite noticeable. Does your vehicle benefit from higher octane? Check your owner’s manual to confirm.
*Ordinary fuel refers to minimum detergency gasoline. Based on ASTM D6201 engine testing.
What is TOP TIER™, and does BP’s gasoline with Invigorate® meet TOP TIER™ detergent gasoline standards?
Eight of the world’s top automakers, BMW, General Motors, Fiat Chrysler Automobiles, Honda, Toyota, Volkswagen, Mercedes-Benz and Audi recognized that the current EPA minimum detergent requirements do not go far enough to ensure optimal engine performance, so they created TOP TIER™ which raised the bar to an additive level that is better suited for vehicle performance.
BP is a registered TOP TIER™ retailer and Amoco Ultimate with Invigorate® goes one step further by surpassing Top Tier treat rate levels.
Does BP gasoline have ethanol in it?
By federal and state regulation, nearly all gasoline sold by retailers in the US has up to 10% ethanol blended into it to comply with the US Renewable Fuel Standards as part of the Energy Independence and Security Act. A small amount of BP stations may sell ethanol-free gasoline (which is labelled accordingly), but this is typically used in off-road vehicles like ATVs or boats.
What is Flex Fuel / E85 fuel? Should I use it?
Flex Fuel (also known as E85) is a gasoline-ethanol blend containing anywhere from 51 to 83% ethanol, and can only be used in Flexible Fuel Vehicles (FFVs). At the dispenser flex fuel is clearly labelled “E85” and includes signage that cautions drivers to use this fuel only if they have a FFV vehicle. Check your owner’s manual to confirm whether you have a FFV vehicle that can run on Flex Fuel.
Learn more about Flex Fuel Vehicles on the EPA website.
What is BP Diesel®?
BP Diesel® is a quality fuel for light duty diesel trucks and cars. It can also be used in all on- or off-road heavy duty trucks, as well as automotive, transit bus, marine, and stationary diesel engine applications that require ultra low sulfur diesel (ULSD).
BP Diesel® is routinely tested for compliance with ASTM D975, including sulfur content and lubricity requirements. Like all our fuels, BP Diesel® is backed by our BP Fuel Guarantee.
BP Diesel® may contain up to 5% biomass component. This is standard for most diesel fuel sold in the US and does not require any special labelling.
Please refer to your owner’s manual to learn whether your vehicle requires diesel.
What are biodiesel blends?
Biodiesel blends are standard diesel fuels blended with a biomass component derived from plant oil and animal fats. Just as the government requires ethanol to be blended into gasoline, they also require or promote the blending of renewable biomass components into diesel fuels.
When biomass components are blended at levels between 5 and 20%, the FTC requires that all dispensers be clearly labelled with the following:

Many diesel vehicles can run properly on biodiesel blends. However, there are a number of manufacturers whose vehicles do not recommend blends greater than 5%. Please consult your owner’s manual to learn if biodiesel blends greater than 5% are compatible with your vehicle.
I have a product quality concern. What should I do?
The BP Fuel Guarantee is more than just a statement. In the unlikely event that you experience fuel system trouble due to the use of BP gasoline with Invigorate® (Regular, Silver, or Amoco Ultimate®) or BP Diesel®, we’ll reimburse you for the repairs. Simply call us at 1-800-333-3991 to report the problem. You’ll also need to provide proof of purchase and a mechanic’s repair bill. We’ll review your claim, and any BP fuel-related repairs will be reimbursed to you.