Originally posted by moerom
Could be a boost leak! When it gets cold, hoses tend to contract and move around.
I have a hissing sound too sometimes, and I have to do a test to make sure I'm not losing boost!
It shouldn't be a boost leak because I'm using all new plumbing and silicone cuplings (I just installed a new intercooler yesterday). Plus the sound is far away from the engine. I'll have to find out if the brake system, or tranny uses any vaccum hoses or anything...hmmm...
I'm not going to drive until I get it sorted out though..