There is a camshaft that acts on the valves, and there is a predetermined amount of "play" or slop in the system that is within specs. As the valve seat wears, the valve gets pulled further into the head, and this lessens the "play" as it wears. If it gets too tight and fails to have any play, the valve won't be held tight against the seal and it will leak, lose power and possibly burn the valve. So yea, get it set.
Also may want to factor in timing belt cost and ask about that and water pump as those aer replaced together.
Adjusting hydraulic lifters, also called "setting the valve lash" provides the necessary travel and operation for the opening and closing of the intake and exhaust valves. Most new vehicles use hydraulic lifters, since their operation and design provides an easy and simple method of keeping the valve train in synchronization. You can perform the adjustment with a cold, static engine or during engine idle once the operating temperature has been reached. Adjusting the lifters on a running engine, however, can present a problem with oil splashing upward from the tappets. They make a spring clip to prevent it from getting all over the engine and compartment. Cost vary from city to city Mechanic to mechanic
Hope it helps
Lr
Not at all a big expense most places should do it for $90 -150 including the gasket . Takes me about an hour to do one. If you don't adjust them eventually you could wear the cam possibly although I've never seen any issues from not doing it. If they are too tight then possibly they could've got the engine hot . If they are too loose which is what they should do as they wear they'll just be a little noisy until you get them adjusted if I can help in any other way please let me know hope this helps
Some cars have little hydraulic gizmos to keep the valves more or less where they're supposed to be. Doing without them is, according to some, a tad more precise, but you have to have the valves checked now and then. (On my old Celica, it was a 60k maintenance item.) It will probably run a hair better afterwards.
Hey YA! I am looking at getting an 01 Honda Prelude this month and valve adjustment keeps coming up when people discuss this car and other cars as well. What is this? Does it cost a lot to do, and is it important? Thank you!