2002 Elantra valve noise?

My 2002 Elantra has 91000 miles on it and about 2000 miles ago started developing a rattle at the top end and has progressed to a loud rattle now on startup and after warming up, will quiet down some. I took it to dealer and they changed oil and filter and added oil additive to it. I was told to drive it for a couple thousand miles and see if it quiets down. If anything, it is getting worse. Do the valves need to be adjusted? Please advise.

Thanks.

You cannot adjust the valves on a Hyundai 2.0L engine as it has HLA's (hydraulic lash adjusters) as it is a dual overhead cam engine. The problem could possibly be a sticky lash adjuster or sludge in the top of the engine causing the lash adjuter noise.

thanks K2...I will mention this to the service dept. at the dealership and see if they can address it. Will leaving it as is cause any engine damage?

nope, the Beta 2 has MLA (mechanical lash adjusters). HLA were on beta 1 (1.8l and 2.0l). They cannont be adjusted. A valve job should be doen if it's really is the problem.

In speaking with the shop service manager, he did say the valve lash adjusters could be shimmed on this engine and that they have done several. Not sure whether he is blowing smoke up my shorts or what.

Thanks for the info.