Re: 1985 Audi 4000s idling rich

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Re: 1985 Audi 4000s idling rich

vgf

14 Jun 2008 04:32

>Sometimes the cold start valve leaks fuel on the inside creating a richer
>mixture. ;-)
>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.

Dave,
Thanks for all the input.

These old cars can be a challenge. But than again, everything gets
older from day one....

>>>Is the cold start valve leaking?
>>
[quoted text clipped - 20 lines]
>>>> Yes, it has a cold start valve, unplugging the wire does not cause any
>>>> change, which does not seem right either. Will keep exploring.....

dave AKA vwdoc1

12 Jun 2008 02:46

Sometimes the cold start valve leaks fuel on the inside creating a richer
mixture. ;-)
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.

>>Is the cold start valve leaking?
>
[quoted text clipped - 20 lines]
>>> Yes, it has a cold start valve, unplugging the wire does not cause any
>>> change, which does not seem right either. Will keep exploring.....

vgf

12 Jun 2008 01:51

>Is the cold start valve leaking?

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
minute.

I'll have most manuals, but I think I'll get the Bentley manual for
this 1985 4000s.

>>>hmmm I have not seen an '85-87 Audi 4000 in awhile. The system is a
>>>little
[quoted text clipped - 6 lines]
>> Yes, it has a cold start valve, unplugging the wire does not cause any
>> change, which does not seem right either. Will keep exploring.....

dave AKA vwdoc1	10 Jun 2008 22:20
Is the cold start valve leaking? >>hmmm I have not seen an '85-87 Audi 4000 in awhile. The system is a >>little [quoted text clipped - 6 lines] > Yes, it has a cold start valve, unplugging the wire does not cause any > change, which does not seem right either. Will keep exploring.....

vgf

10 Jun 2008 02:26

>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.

Yes, it has a cold start valve, unplugging the wire does not cause any
change, which does not seem right either. Will keep exploring.....

>>>How do you know it is running rich?
>>>Is it also idling either too low or too high?
[quoted text clipped - 17 lines]
>>
>> marti

dave AKA vwdoc1

10 Jun 2008 00:28

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.

>>How do you know it is running rich?
>>Is it also idling either too low or too high?
[quoted text clipped - 17 lines]
>
> marti

vgf

08 Jun 2008 19:42

>How do you know it is running rich?
>Is it also idling either too low or too high?
[quoted text clipped - 6 lines]
>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.

Dave,

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!

marti

dave AKA vwdoc1

08 Jun 2008 18:41

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.

Signature

later,
dave
(One out of many daves)

> My Audi 1985 Audi 4000 is running perfectly well when warmed up after
> about one minute.
[quoted text clipped - 4 lines]
> I replaced a leaking valve cover gasket, airfilter and sparkplugs,
> checked the idle valve, but have not been able to pinpoint the cause.

vgf	08 Jun 2008 04:01
My Audi 1985 Audi 4000 is running perfectly well when warmed up after about one minute. The problem is rough idle and running rich when starting the cold engine. I replaced a leaking valve cover gasket, airfilter and sparkplugs, checked the idle valve, but have not been able to pinpoint the cause. Any hints would be appreciated marti-

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