Low Engine Noise (Sound Clip)
 

Hi, first post! I'm wondering what would cause a sound that sounds like an engine with low oil? I've always had the sound since I bought the car back in late 01' (with 154k), but since I was changing the oil yesterday I decided to leave it on the ramps and start it up.

I put my ear next to the oil pan and it isn't loud there, but in front of the engine and low is where it's at, like in front of the oil pan or something. kinda sounds like a deisel truck idleing.

93 civic 175k manual trans.

heres is a sound file (click download file in the brown area) I recorded on my cell, engine was warmed up when recorded.

when you rev the engine you can't hear the noise, but when it goes back to idle you can. Someone on another site told me it could be a main bearing, if that was the case wouldn't it have seized up driving it like that for 20k miles?

if anyone can help I would appreciate it, it's a mystery to me, performance is not hundered, nothing else is wrong, it's just kinda bothered my that the engine might seize up or something cause of it.

thanks!

RE: Low Engine Noise (Sound Clip)
 

my sound is out.
i had a noise too.
i always recommend this:
take one belt off at a time and start it and see if the noise is still there.
that is what i did and i figured it out.

RE: Low Engine Noise (Sound Clip)
 

on another forum a couple guys think it MAY be a main bearing, but wouldnt that have given out long before 21 thousand miles? sound has been the same since i got it, not louder or anything.

RE: Low Engine Noise (Sound Clip)
 

i would have thought so to.
may be the alternator bearing