Tow dolly that was stuck by Toyota Previa

Ignition:  The primary source of ignition was likely to be from mechanical sparks created by the tow dolly rubbing against the pavement, as evidenced by score marks on the tow dolly.  Less likely is the possibility of auto ignition on the exhaust manifold or braided metal exhaust pipe covering.  These exhaust system components were fairly distant from the fuel source and not likely to be hot enough.

 Propagation:  The fire likely originated close to the hole at the front outboard corner of the tank, adjacent to the driver's door.  The fire propagated to the interior through the open driver's door.  The passenger door was also likely open at some point during the fire, then closed or nearly closed as evidenced by the burn pattern.  The undercarriage fire was hottest near the leak (left side), but the interior fire was hottest on the right side (likely due to wind direction). Wind direction was confirmed through local weather services. Fire likely initiated immediately, with propagation to the interior almost immediately after the doors were opened.