Ethanol suspect in Corrosion from ULSD


Veteran Member
Jun 4, 2012
2012 Jetta (6MT) - 1000 Mile Club (retired)___ 2015 Jetta SEL (6MT)
Found this while looking for stability issues with ULSD, and apparently there can be a real corrosion issues if the right factors are present.

"Since the introduction of Ultra Low Sulfur Diesel in 2007, a growing number of diesel storage tanks and dispensing systems have experienced unusual and accelerated corrosion problems. The kind of corrosion that might take 10 or 20 years previously was showing up in as little as 30 to 60 days, says Edward English, vice president and technical director for Fuel Quality Services."

"Further investigation found traces of ethanol in ULSD. Ethanol isn’t corrosive, but when combined with water in the fuel, it becomes a “food source” that is conducive to the growth of acetobacter, a type of bacteria. This bacteria converts (oxidizes) ethanol into acetic acid, which is highly corrosive to mild carbon steel."

"Like the plot in a good murder mystery, the task force has found a lot of suspects, but the identity of the culprit is yet to be proven conclusively."