Portland PDX to Quito, Ecuador is available for a few dates Sep-Oct and Jan-Feb for $273 round trip on American Airlines. Most of the flight itineraries force an overnight in Dallas or Phoenix, or weird routings like PDX to Charlotte, then fly back to Dallas for Quito flight or long layovers in Miami.
But this is a real deal bookable on aa.com for $273.19.
Google Flights pulls up departure dates from Sep 19-Oct 7 and Jan 17 to Feb 3 at $273 with more dates in Sep-Oct and Feb-March 2018 at $351 round trip.
Portland PDX – Dallas DFW – Miami MIA – Quito UIO – Miami MIA – Phoenix PHX – Portland PDX
Fri Jan 26 – Wed Feb 7, 2018