A vacuum gage would be more quantitative than "feel". Useful for many diagnostics on your car. Can even use the little one on a Mighty-Mite hand pump, which is also almost essential in the garage. If you suspect the camshaft, run a hose over from the vacuum on another car that has a booster which works, while the other car is idling. Could be a 2017 car, boosters haven't changed.