Hey guys and gals. I have a 2004 chevy optra. When starting the engine cold, I have an engine rattle that sounds internal. After about 30 seconds it starts to go away. After it warms up its fine. Its not a heat sheild noise, but more something internal. After driving it to opperation temp and sitting at an idle, I can hear it faintly. The last couple oil changes have shown no evidence of a problem (no metal in the filter). Any thoughts on this? It has 110,000km.
Thanks in advance
Brad