A: In addition to that, it also has PCV system hence the need for replacement of the air filter with a new one at regular intervals. It is found on top of the carburetor or throttle body, and can be removed by unscrewing its wing nut, pulling up clips from its top, and lifting its cover. The cover should be taken off, followed by removal of the filter element and cleaning of the housing's inside using a clean rag. After that, fit another filter in the housing making sure it sits snugly at the bottom. Lastly, return all hoses and also the top plate without over-tightening on wing nut.