(hmmm…should I really try this, oh, well) Without illustrations this might not be comprehensible, 'coz I’m not a leading light in the manipulation of the English language.
That said, “lifters”:
First we need cams:
A cam can be thought of as a circular thing w/a bump on it. If it is rotated and something is resting on its semi-circular surface, every time the bump comes around the thing resting on it is lifted up and comes back down when the bump has passed.
So, you’re typical auto engine has a shaft with two of these cams per cylinder - the camshaft (which is (small world isn’t it) turned by the timing chain). On these cams rest objects that are called lifters - they’re the things that get lifted as the bump comes around. When the lifters get lifted, so do the pushrods that rest on top of them and through a rocking horse motion they push up one end of the thing they’re in contact with (rocker arms; hinged at their center, when the pushrod pushes up on one side, down goes the other) and this results in the valvestem (thing in contact w/the other side of the rocker arm) getting pushed down. In your typical overhead valve engine this results in a valve opening. If your friend’s car doesn’t have any chrome thingie on the fender that say something like “DOHC” we’re probably still on the same page. If your lifters are not functioning well, your valve timing will be off and the car will run like a sick dog. That being said, if your friend’s car is less than ten years old and it is the same one w/the timing chain problem, if it’s not running at the barely crank scared to take it out on the street level, your friend may be experiencing a major hose down from the Oracle at the Garage.