What are the differences between PG95 and PG91?
PG95 is a 95 Research Octane Number (RON) octane grade gasoline, and PG91 is a 91 RON octane grade gasoline.
What is an octane number?
- Mostly, fuels with a higher octane rating are used in high-compression engines, which have higher performance requirements. The higher the octane number, the more compression the fuel can withstand before detonating.
- Specifically, the octane number relates to the engine’s compression ratio, which is an indication of the anti-knock ratio of the fuel that determines the amount of compression the fuel can handle before it ignites. The Anti-Knock Index (AKI) is the average of a fuel’s RON and Motor Octane Number (MON): (R+M)/2.
- RON and MON are determined by using a special engine with a variable compression ratio, and comparing the knock qualities of a given fuel to that of reference fuels.
What does unleaded gasoline mean?
Unleaded gasoline simply means that the gasoline does not contain lead. Historically, lead was added to fuel to reduce the volatility of the gasoline and increase the octane rating. Since research showed that lead can be toxic, it has been phased out of fuels in most places around the world.
Is PG91 a premium unleaded gasoline?
- PG91 is a regular grade unleaded gasoline suitable for most cars.
- PG95 is a premium grade gasoline suitable for higher-performance cars.
Why there are two types of gasoline? Before 2006, we had only one type.
Historically, the single grade of fuel offered prior to 2006 was a PG95 grade gasoline. In 2006, it was identified that most vehicles in use in the Kingdom did not require such a high grade of gasoline. Therefore, the PG91 grade was introduced to meet the requirement.
What is the best way to change the type of fuel for my car, such as PG95 to PG91?
The octane requirement for an engine varies with compression ratio, geometrical and mechanical considerations, and operating conditions. Always use the fuel recommended in the owner’s manual of your car.
Does putting PG91 in a PG95-compatible vehicle affect the engine and, if so, how?
Using a lower-octane grade petrol than that recommended by the manufacturer risks long-term damage to the engine of older cars. So, there is a chance that using a low-octane fuel in an engine that requires a higher octane will damage the engine, whereas there is no harm in using a higher-octane grade than specified.
Does putting PG95 in a PG91-compatible vehicle improve the car’s performance? Does it extend the engine’s life or improve mileage?
Ordinarily, a vehicle will not benefit from using an octane higher than recommended in the owner’s manual. Unless you’re driving a performance vehicle, you’re unlikely to see any improvements by using fuel with a higher octane, and you will pay more for no additional benefit.
What about different octane numbers (PG92 and PG93)? Some cars are recommending using gasoline with different octane numbers. Geely cars in China, for example, are using PG93. What is the right fuel choice for these kind of cars – PG95 or PG91?
The best advice is to consult with the vehicle manufacturer for the recommended octane rating of the vehicle. In the absence of a vehicle manufacturer recommendation, the safest option is to use a higher-octane fuel than what is recommended, i.e., replacing 93 octane with a 95 octane gasoline.
Why is PG95 red and PG91 green? This is not a practice in other countries.
Gasoline is injected with a dye to allow for the easy visual determination of the different grades of gasoline (PG91 and PG95) following testing and certification. The different colors are a visual aid to quality control to prevent fueling vehicles with the wrong grade fuel, and also as a visual aid to prevent fuel laundering such as selling low-grade gasoline as a high-grade gasoline. The practice of dying products for visual identification is common in most countries.
How do I find out right fuel choice for my car?
If you’re not sure of your vehicle’s correct octane rating, check the owner’s manual or ask the manufacturer or dealer where you purchased the vehicle. Sometimes, the recommended fuel is also displayed on a sticker inside the filling cap.
What is the difference between RON 91/RON 95 and AKI 87 in Saudi Arabia, and RON 91 in the United States and Canada? This question is mainly for imported cars from Canada and the U.S.
- In the U.S. and Canada, octane is measured by the AKI. In other parts of the world, including Saudi Arabia, octane is measured by the RON or MON.
- AKI is the average of a fuel’s RON and MON: (R+M)/2. In the U.S., the fuel grades range from 87 to 91 AKI octane, which is equivalent to a 91-95 RON octane. For example:
What are the sources of the information on mycar.saudiaramco.com website? Are they accurate? What should I do if I discover a difference between the information in this site and other sources (vehicle dealer, vehicle manual….etc.)?
We gather information on recommended fuel choices directly from Saudi-based automotive dealers. While we make every effort to ensure accuracy, the best source of information is always your automotive dealer.
How frequently is the mycar.saudiaramco.com website data updated?
We annually update the website following the release of new models of cars, and we also update this FAQ page and other website information periodically as required.