We had a bad forest fire season last summer. I got around to changing the Fram Extra Guard air filter in my 2005 Taurus. I happened to have the results from a UOA showing 28 ppm Silicon after 6 months and 5000 miles but the air filter was in in place since last April including the summer filled with choking smoke from the fires. Wondering if some of the fine smoke particles made it past the filter.
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