RE: '83 UrQ 4000rpm and NLS parts needed

["Buchholz, Steven" <Steven.Buchholz@kla-tencor.com>]

>      My black '83 Quattro Coupe and I are still sorting things out. The (
> I'm
> guessing )
> fuel pump still cuts out at around 4000 RPM , but when it doesn't, the car
> flat throws
> you back. I think the problem might be temperature related, and hope a new
> idle switch and what the hell, a new full throttle switch will cure it.
> The
> switches are right over the turbo. All seems right with the air temp
> switch on
> the intake, all connectors short of those in the fuse box and the ECU have
> been cleaned.
>      I need to obtain 2 parts : 443 906 277 idle switch and 411 927 211
> full
> throttle
> switch. Mine are probably original and one or both might be shorting. My
> dealer tells
> me these are now obsolete. Does anyone have any suggestions or have these
> new
> on hand?
> 
... well, since the old ur-q used discrete microswitches for Idle and WOT it
may not be that big a deal to find replacements ... but my recommendation to
you is not to shotgun the problem.  There are websites that describe the
problem and how to troubleshoot it (Scott Mockry's and the Intended
Acceleration site), and it is possible to get the Quattro Turbo Coupe
Introductory Service Training documents from Dyment distribution as well.
The IST documents describe all of the things that can cause the F/TCU to go
into "safe" mode and not allow the engine to rev beyond 4k.  Probably every
QTC owner [who still has a WX engine] has experienced this problem from time
to time.  IME it has always been a problem with an electrical connection
(usually ground) going bad.  In my 12 years experience as an owner of a QTC
I have yet to replace anything in the ignition/fuel injection/OXS system
other than the OXS, spark plugs, distributor cap and ignition wires.  I am
thinking that the Hall Sender unit in my distributor (or perhaps one of the
flywheel senders) is now developing a problem when they get extremely hot
...

If you are convinced that it may be the microswitches it is quite easy to
test them with an ohmmeter ... if they don't register very close to -0- ohms
when closed or infinite when open (with the wiring harness disconnected)
then they are not the source of your problem.  If you are still trying to
sort things out and have not cleaned up all of the ground connection points
and checked both the ground connection point at the back of the intake
manifold and braid from the engine block to the frame on the driver's side
motor mount, do that now and see if you haven't fixed your problem.  

HTH!
Steve Buchholz
San Jose, CA (USA)