re. More '89 200q power problems

Ben Swann bswann at
Tue Dec 10 23:30:51 EST 2002


The warmup regulator which is standard on the '86 on 5000 turbo/turbo
quattro is not boost sensing.  There is a port for atmospheric pressure
comensation.  Therefore you have the right one on your engine.

There is a way, discussed in Probst - BOSCH FI & engine management, that
uses the one described by Huw which is installed in the earlier CIS cars,
like the '83-84 5 cylinder coupe.   I suppose it could be retrofitted and
made to work for boost enrichment.

I actually started to try it earlier when I was ironing out some problems
that seemed to be pressure related.  The car ran worse, and I did not
follow through since it was not my objective.  The problems I had were
actually 1) Bad injectors (they were only a year old viton tipped 2)
Oxysensor going bad 3) Relatively new multi-function temp sensor going bad
again 4) I had the Bypass valve plumbed incorrectly.  Probably I had blamed
a lot of this on the small manifold crack that prompted me to do
essentially a major overhaul, but I am now pleased with the results.

In short on the turbo CIS variant (someone referred to it as the VW version
of CIS Motronic(Javad?) and I think that is a great description even if not
100% technically correct)  fuel enrichment is controlled by various inputs
mainly O2, RPM, boost pressure measured at the ECU port, Multi-function
sensor, and of course the warmup regulator.

I hazard to guess that I could actually make the regulator with the extra
enrichment port(s) work, now that I have the other issues ironed out, but
will follow through with using the extra injector which takes system
pressure pre fuel distributor that I went throuth the trouble to install.
 Eventually I'll get around to finishing my projects, after of course I am
most of the way through the other ones that get forced on me in the mean

Fuel pressure testing can help if all else has been ruled out, but more
often than not it is like a wild goose chase.  Hope this helps, and not
confounds your diagnosis.


[Again thanks for all the help so far, upon further inspection of the whole
thing today most of the intake hoses are actually in better shape than they
appeared, and with the system plugged on both ends and pressurized only a
few places leak.

My current quandary may seem incredibly stupid, but WTF.  Should the
control pressure regulator on this car be a boost sensing unit with the
couple little aux inputs on the side.  Because it isn't.  And onceagain
thanks to the pitiful Bentley manual, I have no real idea, let alone what
and where said lines would hook to if they were there.  I mean page 25.3
pictures a regulator with the ports, but nowhere can I find an illustration
of where they would connect.  I have an old 80-83 5kt regulator, will this
work if indeed it should be plumbed to sense boost?  Or is boost enrichment
electronic on this car via the O2 sensor and frequency valve?  I swear this
manual is worse than my Corrado manual and that says something.  I mean the
pictures on 25.5 don't have anything to do with my car, and I fail to find
an illustration anywhere showing the wastegate frequency valve plumbing in
a realistic sense, page 26.5 provides a pitiful block diagram, 21.3 again
has nothing to do with my car as far as the details go.  What a POS, I've
seen better Chilton manuals.

Sorry to vent but I'm having a hard time believing I pad $110 for this set
of junk.

Thanks as usual.
janders1 at]

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