Is it okay to add fuel additive after filling up the tank?
4 Answers
It is acceptable to add fuel additive after filling up the tank, but the mixing effect may be less optimal. The correct method is to add the fuel additive before refueling with gasoline, as this allows for thorough mixing under the impact of the gasoline flow, thereby achieving better performance. It's worth noting that while fuel additives can indeed improve fuel characteristics, prolonged use may have varying degrees of impact on the vehicle. There is also another type of fuel additive that works by increasing the fuel's anti-knock properties to reduce the likelihood of engine knocking. However, long-term use of this method can easily lead to carbon buildup and increased fuel consumption.
As a seasoned long-distance driver, I use fuel additives year-round. The best practice is to add the fuel additive first, then fill up the tank—this ensures thorough mixing from the fuel flow during refueling. If you've already filled up, adding the additive afterward still works, but remember to drive about 10 kilometers immediately to help them blend. I drive a direct-injection engine model, and following the manual, I pour half a bottle before each refueling, using it once every 5,000 kilometers. However, keep in mind that fuel additives are just that—additives. For new cars in their first two years, they're generally unnecessary; wait until after 30,000 kilometers to consider using them. Also, be careful not to pour the additive into the wrong compartment—I once saw someone embarrassingly pour it into the windshield washer reservoir.
After studying the fuel additive instructions, the sequence isn't actually that crucial. You can pour it directly into the tank after refueling without issues, but the key is maintaining the right ratio. For my 50-liter tank, using one bottle per full tank is perfect. However, avoid continuous use - it's best to apply it every few tanks. The important thing is that fuel additives take about 200 kilometers to fully take effect, so drive normally after adding it. Also, adding it when the engine is cold yields better results. Don't just pour it at the gas station and leave immediately - remember to tighten the fuel cap securely. I mainly use it for carbon deposit cleaning, and after three years of vehicle use, I've noticed significantly smoother throttle response.
My experience is that it's perfectly feasible to add fuel additives after filling up the tank. The gasoline in the tank is already in a flowing state, and it will naturally mix evenly when you drive. Once I forgot to bring fuel additives, bought some at the gas station and poured it directly into a full tank, and the car still ran smoothly. But be careful not to overuse it - half a bottle is enough for a small tank. Choosing reputable brands is also crucial; I once used a no-name brand that caused the engine warning light to come on. Also, remember to replace the fuel filter regularly, as using fuel additives in older cars can loosen deposits in the fuel system and clog the filter. Now I use it every six months, and the idle vibration has noticeably reduced.
