Quick Answer
To verify the quality of fuel stored in your vehicle, check the fuel's appearance, smell, and stability by performing a visual inspection and sniff test. Ensure the fuel has not degraded or been contaminated by examining the fuel's color, clarity, and odor. Use a fuel stabilizer if the fuel has not been maintained properly.
Visual Inspection
When performing a visual inspection, check the fuel’s color, clarity, and consistency. Gasoline should be a clear, light yellow to amber color. Diesel fuel should be a dark brown to black color. If the fuel has a milky or cloudy appearance, it may be contaminated or degraded. Check the fuel’s consistency by looking for any signs of separation or sedimentation. If the fuel has an unusual texture or is separated into distinct layers, it may be contaminated.
Sniff Test and Smell
Perform a sniff test to check the fuel’s odor. Gasoline should have a characteristic pungent, slightly sweet smell. Diesel fuel should have a strong, earthy or sulfur smell. If the fuel has an unusual or unpleasant odor, it may be contaminated or degraded. Avoid using the fuel if it has an off smell or an odor that is significantly different from the standard fuel scent.
Fuel Stabilization
If the fuel has not been maintained properly or has been stored for an extended period, it may have degraded or become contaminated. To stabilize the fuel, add a fuel stabilizer according to the manufacturer’s instructions. Mix the stabilizer with the fuel and let it sit for the recommended time before checking the fuel’s quality again. If the fuel still appears or smells contaminated, do not use it.
Find more answers
Browse the full Q&A library by topic, or jump back to the topic this question belongs to.