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?

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

__________________
James A. Harris

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

__________________
John Shellenberg
1998 C230 "Black Betty" 240K

http://img31.exs.cx/img31/4050/tophat6.gif

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

__________________
1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

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

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

__________________
John Shellenberg
1998 C230 "Black Betty" 240K

http://img31.exs.cx/img31/4050/tophat6.gif