Hi all,
New here - just picked up an '01S that I'm really loving. I introduced myself in the appropriate forum elsewhere. Hi! Anyway, the car currently only has two issues, which may or may not be the same one. One is a small groan/hum on-throttle from idle coming from the intake. Most noticeable when you're trying to maneuver in a garage and the sound of it bounces off the walls at you every time you just barely touch the throttle. This one I know is from the intake because it's easy to reproduce and I pulled the engine cover and had someone do it while I stuck my head under there. Another, similar noise, which I would describe again as a groany hum, at speed, mid-throttle. This one I'm less sure is coming from the intake, but with the top up and the engine cover off, it's pretty clear. With the top down it sounds like it's coming from the front right air vent. It goes away if you get on or off the throttle. Sometimes it will go for days without doing it - it seems to do it less in cold weather - and then some days it will do it reliably, all day long - like today, which was almost 70 degrees here. It's MUCH louder with the top down. It's always exactly the same pitch, and it has a kindof rattle in it too, as if there were a bad fan bearing and the blades are hitting the edges of the tube it's in or something. I've recorded it - you can just hear it in the background over the road and wind noise in this file:
http://insanetechnology.com/weird_boxster_midthrottle_hum.mp3
My first thought after some quick searches is the AOS, but I'm not entirely convinced. Thoughts?
Thanks in advance,
-Josiah