two 4000q questions

[Megan Bigelow]

do you know what the locked rear diff feels like? when you turn, the car will
hop violently, like the tire is skipping over the pavement. if not, get under
the car and manually lock the diff to experience this, so you know that the
rear diff truly is not locked, and the case is not just a burnt out bulb. there
should be a long nasty rusty rod there, you push it towards the rear of the car
to lock it. although ive never heard of this, maybe the rod is so rusty that it
isnt engaging the servo? who knows.

then, while you are under there, you can look at the servo so see if the
suspected vacuum leak is at that servo. i think there are 2 nipples that vacuum
lines attach to, i know there is at least one. the lines might be disconnected
or the nipple might be broken. you could also follow that line as far as you
can to see if there is an obvious leak or cut. on my 4kq, the front servo for
the center to lock is broken, the nipple got broken off and until it gets
replaced, there will be no diff lockin' here!

hth as usual.

megan

Ti Kan wrote:

> Nimmer, George writes:
> > I have a 1985 4000S quattro.  There are two problems I'm looking for
> > advice on.
> >
> > 1. when the engine is cold (e.g. first thing in the morning) i go to
> > start it, and it starts up immediately.  when the engine is warm (e.g.
> > I'm running errands, and making many short trips), it takes two or three
> > tries to get it running.
>
> Another common question that a search of the audifans archives would have
> yielded your answer.  Anyway, possible culprits are leaky fuel injector(s),
> out-of-spec fuel accumulator or fuel pump check valve.
>
> > 2. the rear diff does not lock.  I've tried putting the switch to
> > position "2" and driving slowly, quickly, in reverse, going straight,
> > turning, etc... and it will not lock.   The center diff lock works
> > great.
>
> How do you know that it will not lock?  Just by the light on the panel?
> Maybe it's just a bad bulb or something.
>
> -Ti
> 01 S4 2.7 biturbo quattro
> 84 5000S 2.1 turbo
> 80 4000 2.0
> --
>     ///  Ti Kan                Vorsprung durch Technik
>    ///   AMB Research Laboratories, Sunnyvale, CA. USA
>   ///    ti at amb.org
>  //////  http://www.amb.org/ti/
> ///