In tank, fuel pump may be making a straining noise. Diesel fuel requires additive blending or ?winterization? to be useable at low temperatures. At temperatures below 20° F (-7° C), No. 2 Diesel with insufficient winterization blending may lose its fluidity due to wax separation. This may clog the fuel filter or in-tank filter, preventing the engine from operating properly.
No. 2 Diesel is blended by refineries to various levels of winterization (minimum useable temperature) based on month, geographical location, and the 10th percentile minimum ambient air temperature for the given region. Although rare, during sudden periods of extreme low temperatures (record lows), fuel stations may not be adequately prepared with No. 2 Diesel fuel with sufficient winterization to resist wax formation or ?gelling?.
