c 230 engine noise?
 

I have a 1988 c230 with 73K miles. Car runs very well but it makes a noise amd i am not sure from where....its not easy to describe but here it goes..
its not a ping or a knock...its like a tapping noise and it starts once the engine warms up. it doesnt do it when i start the engine. it takes a couple of minutes. If i stand over the engine with the hood open it looks like its coming from the engine area but if I stick my nose under the car it sounds like its coming from under the car. hard to pinpoint. Opinions?

Piston Pin Slap
 

It sounds like you might have piston pin slap...Jim

Normal. It's some valve that I can't recall it's name right now. Many people visit the dealer about it.

Let us know when you remember the name of the valve. My car makes a rattling noise and the dealer told me to run REGULAR. Maybe they don't know about the valve...

Mike

It's not a rattling noise, but a tick-tick-tick noise. Try searching?

Try "hot idle tick noise" or something like that.