I know that post topic sounds terribly vague, but it pretty much describes where I am trying to figure out cause of this sound. It has been there for the three months I've had the car, but it is getting a little louder. It is hard to describe--it's a kind of pulsing, fluid sort of sound that I hear most clearly from inside the car when I'm sitting at idle, but you can also hear it if you open the door. I think it might come from the transmission, because you don't hear it as much if the hood is open and your standing over the engine. The transmission seems to run fine--perhaps a little bump when it is cold shifting out of first gear, but other than that, no problems. This sound, however, does not sound normal. I changed the tranny fluid when I bought the car, and that made it shift more smoothly, but it had no effect on this sound.

For lack of a better word, the sound is kind of "squirmy," and not totally regular. I almost want to say it sounds more organic than mechanical, which obviously isn't the case... It sort of comes and goes, and is somewhat high pitch. Would something inside the transmission make a weird noise like this? It does not seem to be affected by revving the engine, as it is still there if I leave the car in neutral and put on some gas, or even if I'm driving--it just gets harder to hear over the other motor sounds. I know this description isn't very detailed... but I thought I'd try to see if anybody had a similar noise before bringing it to the mechanic.

thanks