|MadSci Network: Engineering|
Hello, Roger! You are correct that flowing fluids can and do build of static charges (the phenomenon is called triboelectric charging). This could be either the coolant in your system or air blowing over the radiator while the car is in motion and/or the fan going. It is frankly amazing to me that this is occuring. I suspect, not knowing what kind of car you have, that some grounding strap(s) somewhere is(are) either missing or disconnected. You might try putting a grounding strap from the metal of the radiator to the ground side of your battery. The engine block should already be solidly connected to the ground side of the battery (check that connection, too). I'd also strongly advise calling up the manufacturer and telling them what is going on. They will be far more able to advise you as to the specifics of your make and model of automobile than I can.
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