I'm guessing you have alot of miles...
clean clean clean...then heavier oil...
carb cleaner in the throttle body, flush the oil with engine flush(CHEMTOOL B-12 LIQUID is best) and an oil change...20W-50 minimum with an additive like LUCAS and some oil stop leak which may help seal the worn valve stem seals...
If you plug the hose, you'll have problems...
good luck..