Faulty Proportioning Valve ?

[Joshua Van Tol]

Actually Rod at thepartsconnection.com had them for my type 44. Still 
expensive, but not as bad.
On Nov 12, 2004, at 6:58 PM, Fred Munro wrote:

> I don't know if the '90 uses the same lever-actuated rear proportioning
> valve used on the Type 44 (a spring attached to the rear control arm 
> moves a
> lever on the proportioning valve which adjusts the valve position for 
> load),
> but if it does, they seize up in rust belt application. To check it, 
> try to
> move the lever by hand. If it doesn't move, valve is pooched. If it 
> does
> move, put your hand on the lever and have someone apply and release the
> brakes. The lever should "kick". If it doesn't the valve is pooched.
>
> The only source for replacements is the dealer for mega $$$.
>
> HTH
>
> Fred Munro
> '94 S4
>
>
> -----Original Message-----
> From: quattro-bounces at audifans.com
> [mailto:quattro-bounces at audifans.com]On Behalf Of Greville Bowles
> Sent: November 12, 2004 4:50 PM
> To: Quattro List
> Subject: Faulty Proportioning Valve ?
>
>
>
> Well, we have started to narrow down the possibilities re: the rear 
> rotor
> corrosion problem on my '95 90Q. First some background:
>
> New rotors & pads all round - Fall 2002
>
> Replaced rear wheel bearings - Summer 2003. There was no apparent brake
> problem at that time.
>
> Oct. 2004 - replaced very noisy right rear wheel bearing. Left side is 
> ok.
> During that work it was apparent that there was a problem with the rear
> brakes, in that the rotors we very corroded and making minimal contact 
> with
> the pads.
>
> Last weekend - Replaced rear rotors, cleaned and inspected calipers,
> replaced rubber booties. Observations:  Pads only lightly worn. While
> tightening the wheel bolts the real wheels could be turned by hand 
> with the
> brakes applied (read: 0 stopping ability) The hand brake functioned 
> fully,
> solidly locking the wheels. The front brakes are working well.
>
> So, I'm thinking it's time to look at the hydraulics, and my first 
> guess is
> a faulty proportioning valve. Bentley tells me to use the VW1310 tool 
> (a
> pair of hydraulic gauges on a stand) to simultaneously measure the 
> pressure
> at the left front & left rear bleeder valve. If the pressure is 
> outside the
> given range, replace the proportioning valve. Since I don't have the 
> VW1310
> tool, this sounds like a dealer visit.
>
> Before I go to the dealer, is there anything else I should look at 
> that will
> help to diagnose the problem? Any BTDT's?
>
> The following is more background just in case there is some 
> relationship
> that I'm not seeing. It may mean something to others.
>
> Once I get the brake issue(s) resolved I'll need to find out why that 
> rear
> bearing went so quickly (24,000 miles). The noise started during a 
> trip to
> NC. I had the alignment done down there and the mechanic said that the 
> rear
> wheels were way out of alignment. Alignment was done less that 1 year 
> prior
> and I've had no "incidents" since then. I assume that was the cause of 
> the
> odd wear pattern on my new tires (1-2 inch wide bald strip on the 
> inside
> edge of the rear tires).
>
> Another item I need to look at is amount of play in the drive train to 
> the
> rear wheels. I can turn the wheels 3 to 4 inches with little or no
> resistance. Is this normal? Perhaps the CV joints are worn? Or the
> differential?
>
> The clutch release bearing is getting rather loud. I suspect that will 
> need
> attention soon. What all should be done "while we're in there"?
>
> Every time I do something on this car I'm into the great unknown. If 
> not for
> the helpful folks on this list and my good buddy George, I'd be 
> spending a
> fortune at the dealer (or driving a Kia). Thank you 1 and all for 
> keeping my
> sorry ass out of a Korean tin can.
>
> ****************************
> I just called the dealer.
>
> Clutch job (disk, pressure plate & bearing) = $1100 + tax
> Proportioning valve $200 + $126 labor + tax
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Mr. Greville H. Bowles
> RR 5, Rockwood, Ontario N0B 2K0
> E-mail:   zaphod at cansafe.com
> '95 90Q
> '85 245
> '83 GS650GL
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
>
>
> _______________________________________________
> quattro mailing list
> quattro at audifans.com
> http://www.audifans.com/mailman/listinfo/quattro
>
> _______________________________________________
> quattro mailing list
> quattro at audifans.com
> http://www.audifans.com/mailman/listinfo/quattro