How to Check Gasoline Quality?
4 Answers
Methods for testing gasoline quality are as follows: Gasoline color identification: If the color darkens, it indicates the gasoline has been stored for too long and has undergone chemical reactions; Smell test: Gasoline has a faint aromatic odor due to the presence of aromatic compounds in it. You can slightly sniff the gasoline to detect its smell; Actual measurement: Measure the octane number and density of the gasoline. Theoretically, the higher the octane number, the more resistant it is to burning. Meanwhile, gasoline density is better between 0.735 and 0.745. Currently, gasoline at gas stations is generally National Standard IV gasoline, with an octane number typically between 93% and 94%. There is also National Standard V 92-octane gasoline, with an octane number generally between 92% and 93%, as well as higher-grade 97 and 98-octane gasoline.
Before refueling, I usually check the transparency of the gasoline. Good gasoline should be clear and transparent. If it appears cloudy or has suspended particles, there must be something wrong. I also smell it—regular gasoline has a unique fresh fragrance. If I detect a pungent sour or musty odor, it's likely adulterated with impurities. Once, after refueling at a small gas station, my car felt particularly sluggish and fuel consumption increased. A mechanic later told me it was due to excessive gum content in the gasoline. Now, I always carry a small glass bottle to collect a sample when refueling. After letting it sit for a while, I check if there's any sediment at the bottom—this trick works quite well. Additionally, reputable gas stations always have quality inspection reports, so directly asking to see their latest quality test records is another effective method.
I have a down-to-earth method to check gasoline: dip a white tissue into some fuel and observe the color after it evaporates. Good quality fuel leaves light yellow stains, while dark brown residue or sludge indicates substandard fuel. Additionally, I pay close attention to my car's condition after refueling: Is the engine idling smoothly? Are there knocking sounds during acceleration? Is black smoke coming from the exhaust pipe? These are all signs of poor fuel quality. I remember last year after using low-grade fuel, the spark plugs were completely fouled with carbon deposits, and the mechanic said excessive impurities had clogged the fuel system. Now I only refuel at major brands like Sinopec – they clean their storage tanks frequently and maintain stable fuel quality. I also recommend keeping receipts after refueling so you can file complaints directly if issues arise.
The most accurate way to measure gasoline octane is with professional tools. I always keep a simple tester in my car—just insert the probe into the fuel tank opening to get a reading. Any value below the gas station's labeled octane is considered substandard. Another practical method: Before refueling, draw some leftover fuel from the bottom of the tank and check for color separation. Good gasoline won’t separate; if there’s a clear dividing line, it indicates contamination. Also, listen to the engine after starting—good gasoline burns completely, resulting in smooth engine sounds. If you hear metallic knocking, it might be engine knocking caused by poor-quality fuel. Recently, news reports revealed some unscrupulous vendors mixing low-grade fuel with automotive fuel, so extra caution is needed when purchasing.
