Hello Scotty! I have a 1998 Subaru Forester with automatic transmission and 309,000 miles on the odometer with original motor. On cold starts there is a rattle from the engine for about 5 to 10 seconds then goes away and is not present when starting the engine warm. What could it be?
A 1998 Subaru has timing belts which would not rattle. I suspect at that age and mileage it's valve clatter due to the hydraulic valve lifters being worn with them taking a while to pump up when the engine is cold.
Can you upload a video demonstrating the noise to youtube or a file sharing site and post the link here?
Your timing chain set needs to be replaced, right away. Chains should have been replaced at around 150,000 miles.
Sorry about that. How about worn out belt tensioners and idler pulleys?
Could be - I'm hoping at that mileage those have been changed out at least a few times now. If they haven't been they need to be replaced ASAP!