Diverter Valve issue on a 2000 passat

Question

When i disconnected my Diverter Valve and made it non-recirculating i drove down the street and my engine cut out on me. it will go a few feet and after the excess pressure is released (PSHH) the car cuts out. i reconnected the valve tubing making it rec-circulating and it works fine. im baffled i know VW is supposed to run a DV but last night i saw a stock VW GOLF running blow off and he was stock. any ideas? it is an after market DV made by forge.

Answer 1

Yea... The 1.8T is made so you have to recirc your dv. You can run a BLOW OFF valve off of your throttle hose, but thats a lot of redirecting and work for some silly extra noise. Chip that Passat to get some more turbyturbo noise.

Y was there a stock golf with a dv? I'm confused...

Answer 2

The OEM valve has a very low spring rate against the diaphragm holding the plunger down. The very first time you released the throttle the engine  vacuum easily held the valve open.  When not in boost the open valve will become an intake leak because its bypassing the MAF (mass air flow) sensor.  If the MAF reads very low air coming in through the it, the ecm will start lowering the injector pulse width until it cant compensate any longer and will cut off because of the air leak.

The Golf was running a higher spring rate to keep the valve closed at idle or has a chipped ecu to be able to release to atmosphere. Hope this helped out.