When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Further investigation leads to 2 holes (factory, not damage) on the side of the air filter/intake. Covering the holes makes it worse, removing the filter makes it worse
Just guessing, since I've never seen one of those, but could be for the crank case ventilation system. Are there any loose hoses nearby? You should find what went to the holes, and hook them up.