How do you know it is running rich?
Is it also idling either too low or too high?
Check your coolant temperature sensor for the fuel injection.
Check for a weak ign coil.
Check the fuel pressure and the current to the fuel pressure regulator.
Check the fuel distributor flap level according to the Bentley. Oh and
clean that area too! ;-)
I have seen bad/leaking fuel injector seals cause some idling problems too!
You can spray some carb cleaner at them to see if the idle changes any.
On Sun, 8 Jun 2008 13:41:15 -0500, "dave AKA vwdoc1"
Yes, it is running rich because you can smell the excess gas and the
engine stutters, most likelybecause the combustion chamber is
temporarily flooded with gasoline.
Thanks for the tips, they make good sense!
hmmm I have not seen an '85-87 Audi 4000 in awhile. The system is a little
different than my '83 Audi 4000S.
Is there a Cold Start Valve that might be staying on a little too long?
Maybe you could try unplugging it electrically and starting the engine cold
to see what it does.
On Tue, 10 Jun 2008 17:20:28 -0500, "dave AKA vwdoc1"
I don't see any outside leaks. Now, I just looked at my 5000s Bentley
Book and it talks about the throttle switch. There is a throttle
switch on this 85 4000s also, when I disconnect the connector the idle
speed zooms up.
The adjustments seem pretty convulated. I think I'll just put up with
this, since the car runs perfect once it warms up in about less than a
I'll have most manuals, but I think I'll get the Bentley manual for
this 1985 4000s.
Sometimes the cold start valve leaks fuel on the inside creating a richer
I think the Bentley manual instructs you on how to check them.
Yes it could be a problem with the throttle switches, one for idle and one
for wide open throttle....if so equipped.
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