I have an '05 Sunfire with 87K miles on it. I recently noticed on start up after it has sat overnight or several hours a quick (3-5 seconds) rattle in the valve train. After it starts it quiets down. I have had no other issues with how the engine runs. Is this a serious issue or a common occurrence on Ecotec's. I'm worried there may be an oil starvation issue that could lead to terminal damage. I also wanted to know if this is a zero clearance engine, or in other words if the timing chain breaks do the valves drop and come into contact with the pistons? Any help would be appreciated.

Does anybody have any ideas or is this a typical issue with Ecotec engines. My Cavalier I had before this Sunfire was a '97 with the 2.2 non-Ecotec. I just want to make sure I don't do any damage to the engine by ignoring this occasional rattle at start up.

What weight of oil are you using, and what brand?


- 2004 Cavalier - 124k, owned since new

I am using 5W30 Mobil 5000 conventional oil.