Engine "Flapping" Noise

[willfxp]

I noticed when I start my engine, it would make this "flapping" noise. Like if some belt was hitting something. But it goes away after a few seconds. I can't figure out where the noise is coming from. This only happens if I don't drive it for a few days. If I start it up the next day, it won't make the noise. Everything else seems perfect. Any ideas? Thanks.

[mmmikkke]

I noticed when I start my engine, it would make this "flapping" noise. Like if some belt was hitting something. But it goes away after a few seconds. I can't figure out where the noise is coming from. This only happens if I don't drive it for a few days. If I start it up the next day, it won't make the noise.  Everything else seems perfect. Any ideas? Thanks.

 

<{POST_SNAPBACK}>

 

 

Here's my idea. If it sounds like a belt, look a the belt. Do a visible check on the belt tensioner with the hood open after it has set for a few days, and see if it is moving when the flapping is happening. (Have somebody else start your engine.) It could be that your alternator or PS pump or water pump are hanging up briefly when cold, and you might be able to see the belt tensioner move if that's happening. If so, consider lubricating, or replacing, the offending unit.