I tried searching for the exact symptoms of what my car is doing and didn’t find exactly what I was looking for. Sorry If I am starting a new thread on what probably is a typical problem.

I just picked up a 93 190e 2.3L. The car runs fine, starts fine, etc. At start up the engine sounds good. After it warms up I will get an intermittent tapping sound from under the valve cover. As soon as it comes it will disappear. I can rev up the engine and the tapping is still there for a moment, then it will go away. Sometimes after I start it, the tapping starts and then goes away instantly, even at idle rpms.

I check oil pressure and it says about 2 on the guage at idle and goes to 3 when when I rev it up a bit. The oil pressure doesn’t fluctuate on the guage between when the tapping starts and stops.

I assume a sticky lifter. I tried using some tranny fluid with the oil to flush things out. Didn’t work. Changed the oil and filter. Then I tried Wynn’s engine cleaner. Didn’t work. An engine flush and new oil and filter. It’s still the same. It doesn’t sound like the timing chain slap sound, however, I could be wrong. This is my first Benz so I am learning.

What I question is how intermittent the problem is. It just comes and goes at free will. Next step is to take the valve cover off and look into it further.

Any advice or what to look for... from anyone would be much appreciated.
Thanks