View Single Post
JFairman JFairman is offline
Registered User
 
Join Date: Jul 2006
Location: S. Florida
Posts: 7,223
Thats the deceleration vlave.
Technically it is a vacuum limiter that bypasses air around the throttle body butterfly when you lift your foot off the gas pedal while slowing down.
It is an emission control and also works in parallel with the slow acting large origonal recirculation type blow off valve or the newer smaller and faster acting C2type recirculating blow off valve letting out turbo overrun air pressure when lifting off the gas between shifts or slowing down after making turbo boost which also lessens turbo compressor surge and helps keep the turbo spooled up between upshifts.

With the intake manifold vacuum line disconnected like in your pic the motor decelerates faster between shifts (a good thing for rpm matching in the gearbox) and pops more from the exhaust with a stock CIS injection system.. which in my opinion is obnoxious while a little burbleing and soft popping is kinda nice and gives the 930 character.

The thin coating of oil in the intercooler is dirty brown and doesn't look like fresh clean oil.
There are many possible reasons for the oil there if it came from your "fresh" turbo
Old 08-10-2010, 11:18 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)