[V8] question about cylinder glazing

[Ingo Rautenberg]

George,

Sorry to hear.  Did they check the fuel pressure regulator? And not just the
regulator, but also the  vacuum hose from the fpr to the intake manifold for
possible blockage (though unlikely).

Yes, a barely reading OXS can throw the metering compensation to super rich.
If you unplug the oxs, it shouldn't run as rich.  The built-in default would
never cause the engine to run super-rich like you describe.

Ingo

----- Original Message ----- 
From: <getur at optonline.net>
To: <dsaad at icehouse.net>
Cc: <v8 at audifans.com>
Sent: Friday, December 08, 2006 11:15 AM
Subject: Re: [V8] question about cylinder glazing


>
>
> ----- Original Message -----
> From: dsaad at icehouse.net
> Date: Friday, December 8, 2006 10:11 am
> Subject: Re: [V8] question about cylinder glazing
> To: v8 at audifans.com
>
> > How much oil are you using George?
> >
> *********
> Up until a few months ago the V8 was burning through about 1 qt per 500
miles. Then the burn rate started going up to about 1 qt per 250 miles. The
car at that point started blowing a lot of blue smoke on startup and also
blowing soot under heavy throttle. I replaced the plugs at the time but the
startup smoke and soot continued. Last week I noticed  that there was a
smell of fuel in the exhaust under heavy throttle. Brought it into the shop
and after pulling the plugs they found that they were soaked in gas. They
ran some checks on the car and found that the oxygen sensor was not working.
I had the heads rebuilt a while back, so I thought that that might be the
culprit for the oil consumption, but a compression check showed that
everything was good, so far as rings and valves were concerned. The shop
thinks that what happened is when the oxygen sensor went bad the system went
into default mode, and was running extra rich, which after a while washed
down the cylinders, caused excessive glazing, and in turn increased the oil
burn rate. At this point they've added an additive that was recommended by
the machine shop to try and reduce the glazing to see if the oil consumption
will go down. The shop said to run it this way for about 2000 miles and see
if it improves. If not then the recourse is to either rebuild, get another
engine or throw in the towel with the V8.
>
> Like Mike says, it's an adventure with this car.
>
> George
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