My 2001 dodge caravan makes a loud whining noise when cranked during cold weather. The colder the temp. the louder the noise & the longer the noise lasts. The noise usually only lasts a couple of seconds. But when its really cold (10 to 20 degrees) it may last 30 seconds. It doesn't sound like a belt is making the noise. It never makes the noise when the weather is warmer. The temp. has to be below 50 degrees before it does it. Any suggestions on what might be causing it?

Noises associated with the fuel/air injection system during cold weather?

It could still be the belt. Or a pulley.
Remove the accessory drive belt and try starting the engine. If the noise goes away, closely inspect the belt and all pulleys. Look for signs of a bearing failure: tiny metal shavings and/or dust. Look also for signs of corrosion.