My Proton Saga's 4G15P engine's distributor cap did not have a gasket, dust got in & blocked electrons' flow from cap's centre pin to rotor. I had to make this gasket myself. Neither does a 6G72 engine's distributor have a gasket, same consequence.
4G15P's petrol pump ( mechanical, fitted to engine ) has no rubber / cork gasket, has just fibreglass gaskets ( too hard, & can disintegrate when soaked in mineral oil ) which cannot seal in the engine's oil. I had to find a rubber skin & cut a gasket myself to stop oil leaking out & onto the floor below. Their designers should be sacked.