[urq] Ideas for rough running continued - Solved!

Thu Apr 7 11:51:07 EDT 2005

The tach needle drops to zero as if the power to it went away.  When
power returns, it pops back to whatever rpm the engine is turning at
the moment.

Ed

On Apr 7, 2005 8:16 AM, Ingo Rautenberg <i.rautenberg at waratap.com> wrote:
> Ed,
> 
> When you say the tach drops, does it drop with associated engine rpm or does
> it just drop to nothing like the power to the tach needle was clipped.  Mine
> would drop, too, but I couldn't discern whether it was electrical or because
> the fuel/air was effectively shut off -- which in my case it was.  Have you
> checked the metering plate for any kind of binding yet?  Mine got
> progressively worse to the point it wouldn't start at all...
> 
> ----- Original Message -----
> From: "Ed Kellock" <ekellock at gmail.com>
> To: "UrqList" <urq at audifans.com>
> Sent: Wednesday, April 06, 2005 9:41 PM
> Subject: Re: [urq] Ideas for rough running continued - Solved!
> 
> > I may have had an "AHA!" moment.
> >
> > I went out the adjust the distributor subsequent to my weekend post
> > and Ingo's response to see if anything changed with my ignition
> > cutout.  It didn't.  The car started easily but sure enough the
> > ignition cutout is still there.
> >
> > As I sat there opening and closing the throttle, I noticed that the
> > cutout seemed to occur as soon as I lifted my foot.  Once in a while
> > it would happen a moment later as the rpms fell.  It did it reliably
> > enough that I believe I can connect the behavior with the symptom.
> > Not high rpm's involved, most of the time it was nothing over 2500.
> >
> > When the ignition cuts out, the tach needle drops every time but the
> > fuel gauge seems to be unaffected.  And the relay in the fuse panel
> > that clicks doesn't do it every time, only when the duration of the
> > cutout is longer.
> >
> > What's the gizmo that holds the idle up a bit until the car warms, the
> > idle control?  I think the temp sensor for mine is somewhat defective
> > because the rad fan had already kicked on once before the idle control
> > let the idle drop down to a more normal warm idle.  As soon as this
> > occurred the cutout started happening by itself repeatedly but not
> > necessarilly enough to kill the engine.  When I opened/closed the
> > throttle to keep it running I found that I could reproduce the cutout
> > much more directly always on decel or lift throttle.
> >
> > Anyway, all of this reminded me of Ingo's sticking fuel plate spring.
> > Now, maybe I'm pairing apples and oranges a bit here, but the
> > similarity is interesting at very least.
> >
> > Is there any relation between the lack of air flow and resulting fuel
> > cutout as in Ingo's case and the ignition trigger?
> >
> > Ed
> >
> > ----- Original Message -----
> > From: "Ingo Rautenberg" <irautenberg at comcast.net>
> > To: "UrqList" <urq at audifans.com>
> > Sent: Saturday, March 26, 2005 5:02 PM
> > Subject: Re: [urq] Ideas for rough running continued - Solved!
> >
> >
> > > It was the Airflow meter.  Now I need to have my exhaust reattached
> > > (currently held together with baling wire).  Really quite
> > remarkable.  After
> > > replacing almost every conceivable possible problematic piece (save
> > entire
> > > engine or turbocharger) with known good, I decided to look at the
> > airflow
> > > metering plate again, which I initially thought was binding, and
> > compared it
> > > with another that I had just recently bought.  What I discovered was
> > that it
> > > was not sticking against the venturi wall, but rather that the pin
> > that
> > > rests on the leaf spring had actually worn a hole in it!  On decel,
> > it would
> > > essentially stick, the pin lodging itself into the hole, choking off
> > air and
> > > fuel.  It would not restart unless I turned the CO screw to richen
> > the
> > > mixture, which would apparently plop the plate up again.  Some pics:
> > >
> > > As seen from below (air filter side):
> > > http://www.dtwaudi.com/album_pic.php?pic_id=2093
> > >
> > > And from above with mtereing plate removed:
> > > http://www.dtwaudi.com/album_pic.php?pic_id=2094
> > >
> > >
> > > I highly recommend anyone who has similar sysmptons look at theirs
> > by taking
> > > off their igloo, removing the air metering  plate (10mm bolt) and
> > inspecting
> > > the "rest" area for wear or wear-thru.  Maybe that's your problem,
> > Ed.
> > >
> > > Ingo (tired but glad I finally found the problem)
> > >
> > > Happy Easter!
> > >
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> >
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