So I was tinkering around on the v90 tonight, and I had to pull the air filter box out. I remembered reading something about a thermostat that can block cold air from coming in. So I decide to check it out for myself.

I can honestly say that it was one of the dumbest feats of mechanical engineering I've seen on a car. Maybe I'm missing something here, but every maxim of automotive performance says that you want as much cold, dense air being fed to the engine at all times. so what purpose does it serve to give your intake the option of pulling warm air from beside the engine block through a restrictive, skinny hose? Am I completely missing something here?

Maybe if the thing was designed to open the warm-air side as a supplement to cold air, I could understand it. But the way it's designed, you're either getting lots of cold, or little bits of warm...

There's no way to tell if the thing was operating correctly in my car, but I'll guess it wasn't working 100% because the hinge was a bit crusty.

So I set the flap to forward feed. Oddly enough, if you flip the airbox over, there's a hole drilled in there that's basically at the Cold-air setting position. It's like some guy in Sweden looked at the design and said "ah, this is bullshit" and gave you a factory way to override the system! I found a black plastic interior panel clip in my toolbox that fit perfectly in the hole. Looks like it's an OEM setup. I also pulled all that lame aluminum tubing out of the engine bay. Seriously Volvo, next time you design a car, let us MBers have a look at it. We could've saved you probably $45 per car built on that bonehead design.