Per instructions here:
http://www.brickboard.com/FAQ/700-900/EngineSensors.htm#ReginaAirTemperatureSensor
I tested the leads in the rear of the MAP sensor while the car was up and running. I applied throttle which decreased the vacuum pressure on the sensor causing the voltage to rise, which means that the sensor is functioning as far as I can tell.
I removed the air temperature sensor from the car and stuck it in the freezer and warmed it up with a hair dryer (aka heat gun ;)) and the resistance did decrease as it heated up.
This leads me to believe that BOTH of the sensors above ARE indeed functioning.
The cold start valve you already explained and I seem to recall that I did pull that code once a few years ago when I checked for codes and got the same response. And the IAC... well, unfortunately it seems to be broken. Now why in the world is the OBD throwing a code for both of those items when they're obviously working? If both the MAP and air temp sensors were broken, in theory my car shouldn't even be running properly. I would think it'd be like having the MAF disconnected in those cars that have it (limp home mode).
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Ken 1990 Volvo 740 base sedan (B230F) My Volvo 'Project'
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