[200q20v] Is it my turbo?

QSHIPQ at aol.com QSHIPQ at aol.com
Sun Nov 19 11:41:24 EST 2000

In a message dated 11/19/00 10:21:11 AM Central Standard Time, C1J1Miller 

> IME, the noise on transition from vac to boost can often be the turbo 
> valve.  The turbo is always spinning, even at idle.  Worth the $45 to see 
> the noise goes away.
>  Chris

Ingo just replaced it, albeit with a TAP unit.  That said Ingo, if you got 
the adjustable preload spring unit, try messing with the preload a bit (add 
more preload).  A weak bypass valve spring tension can give the "blowing over 
a beer bottle" sound you describe.   Er, you might also want to make sure the 
opening opposite the nipple on the stock valve is attached to the low 
pressure side (turbo inlet).   The excessive oil in the end caps doesn't bode 
well for this hope however.  Neither does your bonzai boost levels (hey I 
warned ya - but it sure got us to CO fast this past Aug;)

Further Ingo, if you got one of the early TAP bypass valves (non adjustable 
spring preload), you might have gotten one of the ones with a low spring 
rate.  Since the unit is serviceable, you can add a stiffer spring to it as 
well, Dave Jones or Ivor should have those in stock.


Scott Justusson

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