wierd noise after startup - video

[Z31toZ32]

welp, looks like the old max is finally starting to fall apart. i noticed this happening once in awhile when it starts up cold, but now it is happening just about every time (when cold). right after i crank the car, it starts. immediately after, i can hear a very wierd "vrrrrRRRRRRrrrrr" type rev noise. almost sounds like a vaccuum turning on and off real quick. it only last 1/2 a second or so. i am thinking it is not the starter because that sounds like normal when it is cranking, but i am no mechanic by any means. i am not sure if it is a loose belt that tightens after i start the car or what, but it is making me nervous.

i took a video, but of course it didn't do it very well when i shot the video. anyway, here is the video" http://www.youtube.com/watch?v=RjlWJk3T ... yoFRoJxxqI. i will do it tomorrow again to catch a better noise if there isn't an immediate consensus.

[loystock]

Yes, a better video can help. Too much background noise. Maybe changing with synthetic oil, 0W-30/40 may eliminate it.