cd strangeness & stalling issue
pjrose at frontiernet.net
Wed Jul 13 11:26:45 EDT 2005
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 :-(
mailto:pjrose at frontiernet.net
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