Investigators have figured out the cause of a series of roadside fires in the Palo Cedro and Bella Vista area, and now they’re looking for the responsible vehicle. On Friday and again Tuesday, Cal-Fire and Shasta County Fire Department responded to several small fires burning alongside Deschutes Road. The fires were quickly contained because high humidity levels and high moisture content in grasses means a slow rate of spread for wildfires. Those conditions will quickly change with just a few sunny days and the results could be disastrous. Cal-Fire investigators took a very close look at the fires and discovered fragments of metal that are believed to have come from a disintegrating catalytic convertor. It’s something that eventually happens to every catalytic converter due to high miles or poor engine maintenance. The already very hot-by-design device becomes superheated and fragments are expelled out the tailpipe. Sometimes the only way for a driver to know is when the “check engine” light goes on and a code reader indicates catalytic converter issues. Investigators are hoping to hear from the public about a vehicle that may be the source of the fire-starting fragments on Deschutes Road. Tips can be provided by calling 225-2418.