What if I put regular gas instead of premium? If you put regular gas instead of premium, you may experience a couple of problems. These are including reduced engine performance, lower fuel efficiency, and increased emissions. This is because regular gas has a lower octane rating than premium gas, which means it is more prone to knocking or detonation.
We will describe the details of regular and premium gas and the consequences of using regular gas instead of premium.
Contents
What If I Put Regular Gas Instead Of Premium? Is Regular Gas The Same As Premium?
No, regular gasoline and premium gasoline are not the same. Regular gasoline and premium gasoline are formulated differently, mainly in their octane ratings. Premium costs more but offers performance, efficiency, and engine protection benefits.
Using regular instead of premium is not recommended for vehicles that require premium fuel. While not exactly the same, regular gasoline will work fine for most regular consumer vehicles.
When To Use Regular Gas?
For most everyday drivers, regular gasoline is just fine for their vehicles. Unless you drive a high-performance car like a luxury sedan, sports car, or muscle car that specifically requires premium fuel, you likely do not need to use premium gas. Regular gas works well for most normal consumer cars, trucks, and SUVs, especially older models.
As long as your engine runs smoothly without knocking noises, and your owner’s manual doesn’t state that premium fuel is required, then regular gasoline is a safe, effective, and cheaper choice for your vehicle. For typical driving and commuting needs, regular gas will provide satisfactory performance and savings at the pump for most drivers.
When To Use Premium Gas?
You should use premium gasoline for high-performance vehicles like sports cars or muscle cars that recommend premium fuel. Premium gas is also good for cars with turbocharged, supercharged, or high-compression engines to prevent knocking and maximize performance. If you hear knocking when you use regular gas, switch to premium.
Premium can help when towing or in extreme weather. Follow your owner’s manual – if it recommends premium, use it for the best engine operation. While premium costs more, it provides added performance and engine protection for certain vehicles. For most everyday drivers though, regular gasoline is sufficient. Only use premium when you truly need the extra benefits it provides.
Difference Between Regular And Premium Gas: Regular Gas vs Premium Gas
Let’s see the comparison between regular gas and premium gas.
| Point of Comparison | Regular Gasoline | Premium Gasoline |
| Octane Rating | 87-89 | 91-93 |
| Cost | Lower | Higher (20-30 cents more per gallon) |
| Performance | Lower | Higher power and acceleration |
| Fuel Economy | Slightly worse | Slightly better |
| Engine Knocking | More likely | Less likely |
| Components | Okay for most cars | Required for some high-end/performance vehicles |
| Who Needs It | Most regular consumer vehicles | Luxury and sports cars, high compression engines |
| Who Doesn’t | No benefit for most cars | Waste of money if regular gas is recommended |
Can I Mix Regular Gas With Premium Gas?
It’s not recommended to mix regular and premium gasoline in your fuel tank. Here’s why:
- It won’t save money
Mixing the two doesn’t average out the octane rating. More premium would still need to be used to reach the desired octane level.
- Uneven octane distribution
The two fuels will not blend evenly, leading to uneven octane levels reaching your engine. This can cause performance issues.
- Possible engine knocking
Low octane areas from the regular gas can still cause detonation and engine knock, even when mixed.
- Reduced performance
The engine will perform at the level of whatever octane reaches the cylinders, which varies unpredictably when mixed.
- More frequent fill-ups
In order to keep the gases suspended evenly, more frequent fill-ups would be required before they separate.
- Increased fuel system wear
Going back and forth between different fuel grades and mixtures can increase wear on fuel pumps and injectors.
The best practice is to choose the appropriate fuel recommended for your vehicle and use only that fuel consistently.
What Will Happen If I Put Regular Gas Instead Of Premium?
Here’s what can happen if you put regular gasoline in a car that requires premium fuel:
Engine knocking/pinging
The most immediate issue is you may hear a metallic knocking or pinging noise from the engine. This occurs when the fuel ignites prematurely due to the lower octane rating.
Reduced performance
You’ll likely notice a decline in engine power and acceleration as the car has to adjust the timing to compensate for the lower octane gas.
Worse fuel efficiency
The engine won’t run as efficiently, so fuel mileage will drop slightly.
Potential engine damage
Prolonged knocking and pinging can cause long-term wear and tear on engine components like pistons and bearings.
Check engine light
The engine computer may detect issues with ignition timing and turn on the “check engine” indicator.
Higher emissions
The improper fuel combustion can increase exhaust emissions. This may set off “check engine” lights related to emissions controls.
The severity depends on the vehicle and how low the octane rating drops compared to the recommended fuel. Using regular instead of premium won’t destroy your engine immediately, but over time it can reduce performance and fuel economy while increasing the risk of costly repairs.
Recommended articles:
- What Happens If You Accidentally Put 87 Instead of 91 in Mercedes
- Can I Put A 24x Crankshaft Instead Of A 58x
- What Should I Use Instead Of Armor All
- Can You Clamp A Muffler Instead Of Welding
Bottom Line
Regular and premium gasoline differ primarily in their octane ratings. Premium fuel provides more power, efficiency, and engine protection, but at a higher cost. For most everyday drivers, regular gas is sufficient for their vehicles. Only use premium for high-performance engines or when recommended.
Mixing gasolines is not advised. Putting regular gas in an engine that requires premium can reduce performance and economy while increasing engine wear over time. Check your manual and use the recommended fuel grade whenever possible.