The valve behind the airbox is the auxiliary air regulator. I've noticed it raises my idle by 200rpm when the microswitch on the throttle body is disengaged. The thing under the ISV is the control pressure regulator and it is a simple bimetallic strip that allows less control pressure to get to the control plunger and thus enriches the mixture in cold conditions. All these are not as effective as the CIS-E in cold weather and fuel economy is not as good but they do provide better reliability and are simple to diagnose.
----- Original Message ----- From: <[email protected]> To: <[email protected]> Sent: Friday, January 21, 2000 2:11 AM Subject: Re: Diaphragm Pressure Valve > Sorry guys, but you are both wrong. You forget that the 16V's in Europe run > on CIS, not CIS-E. The injection is strictly mechanical. The DPR on Nils' > car is on the side of the cylinder head, just below the ISV. The part that > you are talking about, Alex, is the little white box on the side of the fuel > distributor, and Dave, I know what you are talking about, and it's something > else, and I don't know what it does. The part he's talking about sits on the > left rear of the airbox(if looking at the car from the front). I don't know > what it's for, as I have never actually seen CIS on a 16V. I can't wait for > my next trip to Europe. Anyway, Spoon, you have any idea what this thing is? > And Nils, where does the vacuum line go to? My suspicion is that it is some > kind of altitude adjustment for the fuel enrichment... > > -Dave > '91 GLI 16V > > > In a message dated 1/20/00 11:40:24 AM Eastern Standard Time, > [email protected] writes: > > > << That is the DPR (Differential Pressure Regulator) I forget exactly what > it > > does, but it is part of the mixture control. They are expensive, about > > $250. > > >> > > That isn't the DPR. The DPR is just a little box, right by that > cylindrical > > > > looking thing. If you search long enough through the Bentley, it says > what > > that thing is. I looked it up once, but I forgot what it says. > > > > Alex. > _____________ > List Sponsor: http://www.netsville.com > To remove yourself from this list, send mail to [email protected] with 'unsubscribe a2_16v' in the body of your message > See us on the web at http://www.a2-16v.com > Visit the 16V Homepage at http://www.gti16v.org > _____________ List Sponsor: http://www.netsville.com To remove yourself from this list, send mail to [email protected] with 'unsubscribe a2_16v' in the body of your message See us on the web at http://www.a2-16v.com Visit the 16V Homepage at http://www.gti16v.org
