cd strangeness & stalling issue

[Kerry Griffith]

	Thanks for the detailed information, Phil. You're right about my 
techs; they're far from being monkey lads, but they sometimes err on 
the side of trying to save money for customers (and I imagine there is 
a small element of laziness as well). I called and told them to get a 
CD modulator unit, and they sort of whined about not having heard of 
it, etc. It took a number a tries for them to sort out my a/c even 
though I kept telling them I'd be happy to pay any labor cost involved. 
But they're very fair, very honest, very inexpensive, and all they do 
is Audi.

	I suspect you're right on the ISV as well- I know the vacuum control 
hose of which you speak is quite new and un-baked, and when the BPV 
valve went bad when I bought the car (10 years ago!) the symptom was 
not even intermittent, never mind only once (thus far . . ).
I saw Scott M's directions for removing the ISV and cleaning it, so 
despite being a bit of a monkey lad, I may tackle that myself. Does 
Bentley describe the 9v battery test?
Again, thanks for the patient and detailed response. I'm sure I would 
have been driving something newer (and possibly from the Land of the 
Rising Sun were it not for the long-term fonts of wisdom such as you.

Best Regards,
Kerry


On Wednesday, July 13, 2005, at 09:26 AM, Phil Rose wrote:

> At 7:25 PM -0600 7/12/05, Kerry Griffith wrote:
>> OK, time for my annual questions for you gurus.
>> 1. Recently, the car wouldn't idle- died any time I took my foot off. 
>> Had to restart, sometimes by abusing the drivetrain while in motion. 
>> Scared my eight-year-old (and myself) since it was rush hour. I doubt 
>> it was the bypass valve we've all replaced, since it has run fine 
>> since. I know Scott M. mentions the idle stabilizer valve on his 
>> site, so my question is this:
>> Given the fact that my (good) mechanics have checked out all they say 
>> they can, especially vacuum lines, does anyone have a suggestion? I'm 
>> tempted to throw parts like the ISV in there despite the $$ approach, 
>> but if anyone has a likely culprit, I'd be grateful for the shortcut.
>
> Why consider just replacing the ISV (>>$100) on a hunch, rather than 
> the BPV (under $50)? From what you described, I might not suspect the 
> BPV since you say you merely need to lift off the throttle in order 
> for the car to stall. The BPV symptom usually shows up only when 
> lifting the throttle (and braking hard to stop) while under turbo 
> boost (i.e., just after hard acceleration).
>
>  In any case, both parts can be tested, so I wouldn't replace either 
> one without hard evidence that it's defective.  Perhaps your "good" 
> mechanics have done that, but I wouldn't count on it. The BPV needs to 
> be removed and then it can be determined if there is a leak in the 
> bellows valve. Another (very plausible) source of BPV problems would 
> be its vacuum (control) hose: does it actually hold vacuum or is it 
> split and/or toasted? At least you should remove the large 
> black-painted metal air-intake tube and visually verify that the BPV's 
> small rubber vac hose (that runs between the exhaust manifold and the 
> intake pipe) is not burned to a toasty, leaking crisp.
>
> The ISV electrical operation can be tested with a 9-volt battery. 
> Movement of the ISV valve sometimes becomes sluggish because of 
> oil/dirt accumulating on the surfaces of the valve "cylinder"; it can 
> be resurrected by careful cleaning/flushing with carb cleaner, etc. 
> The ISV needs to be removed for this.
>
> Even "good" mechanics often won't do these things for inexpensive 
> parts because of the time required--they can easily just replace the 
> BPV with a new one at not more total cost than needed to remove the 
> old one, test it and re-install. If you aren't able to take on such 
> diagnostic work yourself, you may be forced to replace things by 
> educated guesswork. That's usually the expensive way to go with 
> maintaining these cars, but you've got to go with what works best for 
> you and your available time and facilities.
>
>> 2. When I attempt to listen to a CD, it will begin to play for 
>> anywhere from 5-30 seconds before the music is replaced by static. 
>> Just had my radio head unit overhauled by Brett Seamens (thanks to a 
>> lister's suggestion), but apparently that wasn't my problem. Does 
>> anyone recognize this symptom?
>
> Yes, that's the symptom I had when the CD player's FM-modulator unit 
> (a small box located/buried in the passenger-side footwell) went bad. 
> Replaced the modulator with a used one and that solved the problem. 
> It's a bit of a problem to access this unit although not that bad once 
> you get the hang of working upside-down with your head on the floor. 
> I'd advise assuming this _is_ the problem and simply to go ahead and 
> replace it with a (_known_) working unit. I was fortunate to get one 
> from a lister who removed it from his own vehicle (being parted 
> out)--however as with many well-used parts, it worked fine for only 
> about a year and now I need another one :-(
>
> Phil
> -- 
>
> Phil Rose
> Rochester, NY
> mailto:pjrose at frontiernet.net
>