Howdy. I have an 83 DL wagon and just noticed a sound in the engine i've not heard before. When I am driving and have the gas pedal engaged it sounds smooth as normal, but when i let up on the gas to coast the engine start making a chugging sound, kind a sharp sound like 2 pieces of paper rubbing together. THen, when i press the gas pedal to pick up speed it smooths out again. Any ideas? Thanks.

very hard to tell without actually hearing it.

by your description it sounds like it may be related to the engine/transmission mounts allowing somthing like the fan to hit the shroud when the engine shifts.

also check the drive shafts for wear or debris rubbing on them.