Unlie every other vehicle in my life, the mx-3 thermostat is not so obvious.. When I follow the upper hose I dont see a clear housing for a thermostat.. Instead there seems to be a cluster of plugs and sensors before it goes to the engine.

any idea where this thing is located?

 

Check the other hose, by the air intake. it's underneath the distributor. tricky spot, in that most wouldn't think it'd be down in there.
easier than an 89 nissan sentra!