Chrysler Repair: 99 Chrysler 300m: tappet noise, tappet noise, valve lifters

Question
Dear Roland
I have a knock in my engine it seems coming from one valve, engine is very stable idle, economic fuel.
My question :
This engine has hydronic valve control or not, if yes is there som oil additive can solve this, if no can I found some thing need adjust (my be rocker gab )
Thank you,,

Answer
Hi Essam,
Which engine do you have: 2.7. 3.2 or 3.5L?
There are some oil additives that claim to dissolve sludge that may be blocking oil to reaching one of the valve lifters which then causes there to be too big a space between the valve that rocker and thus the click occurs. You could try such a product soon before you are planning to change oil, then change the oil. But thare are about 10 other reasons for tappet noise:
too high or too low amount of oil in the crankcase, thin or diluted oil, thick oil, low oil pressure, dirt in lash adjuster, worn rocker arm, worn adjuster, worn valve guide, excessive runout of valve seat or valve face, missing adjuster pivot. You can remove the valve covers and push down on the rocker arms one at a time to find the 'spongy' adjuster and then focus in on that one.
Please 'rate' my answer (see PS below).
Thanks,
Roland