I am not certain what is meant by 'valve train moves' but I will try to help.
If none of the valves has struck a piston only the cylinder head should require work.
If the above has occurred prepare for a large bill. The engine must be removed from the car. It may be a one piston replacement for a quick fix, but having got that far most people will do a complete overhaul.
Variable timing valve train
nope has to be the 32 valve engine
Probably worn valve train parts.
Valve train clatter.
Heads and valve train
There is no valve adjustment for that engine. If you have valve clatter you must have worn valve train parts.
The valve lash is not adjustable on that engine. The rocker arms are bolted down and torqued to specs. If you have valve clatter you have worn valve train parts.
How do you replace valve stems and guides on a 1989 Jeep 4 Cylinder engine?
do you have the 3.0 V6 12 valve engine, or the 3.0 V6 24 valve DOHC engine? 3.0 v6 12 valve
The purpose of the valve spring is to maintain contact between the components in the valve train, so the valve motion will follow the cam profile.