Doe the car have PCV? If not that my be a siphon tube. If it runs down to the bottom of the car, air passes by it drawing crankcase gasses out by "siphon" I have never seen one before on a Mopar, but I know the system existed prior to PCV. the oldest Mopar I have owned was 1969. This is just my guess, hopefully it is close to being a correct guess LOL!