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[youngc]

Hello,

I have an '84 Audi 4000 1.8L fuel injected car that has "fuel
delivery" problems. It will start and drive for up to 5-10 minutes
until it starts to loose power, sputter and hesitate and finally stall.
While these symptoms are present, trying to use the accelerator
actually seems to make the symptoms worse. For example: your stopped
at a light and try to accelerate. This is when it will ususally stall
out.

My local VW/Audi/BMW mechanic cleaned some gunk out of the fuel
pump and I drove the car for 30 minutes until the symptoms returned.
My mechanic says that he is not sure what it is and if he starts
replacing parts it is going to get expensive. He has "confirmed"
that the fuel pump is working at least when idling but not while the
car is being driven.

So, if you might have any suggestions to offer or might know
someone who knows these cars I'm all ears. Thanks in advance for
your attention.

-Chris

[dave AKA vwdoc1]

Does it immediately start back up?

Did you mechanic do a fuel pressure test on your vehicle?
Did he check the current at the Fuel Pressure Regulator? Might be a bad
ground......located at the cold start valve IIRC.
******A lot of times I find that someone removes the fuse to this part of
the system thinking it is a spare fuse.****** lol

Is the fuel filter new? There should be a container near the fuel pump that
is installed in the fuel hose/line from the gas tank to the fuel pump.
Maybe it is clogged.
Usually the pump complains about a lack of fuel by Whining louder.

Maybe there is a serious vent problem and vacuum is created inside of the
tank. Try taking off or loosening the gas cap to see if that stalling
changes.

3 things needed:
Compression
Fuel
Spark

later,
dave
(One out of many daves)


"youngc" <youngc123@hotmail.com> wrote in message
news:1126464635.426418.106000@g49g2000cwa.googlegroups.com...

[Tony]

I mis-posted this in another thread. Bad connection with my Qwest DSL for last
week may have delayed a thread loading or I may have just screwed up.
Anyway >>>

In an earlier thread about an '86 T44 I was suggesting that the problem was the
fuel tank lining peeling off and clogging the fuel pump intake screen
intermittently. I would think that this may be your problem too.

Fix:
-cut intake screen off pump and replace fuel filter more often.

You might also have a weak fuel pump relay.

youngc wrote:

[cp]

[youngc]

Dave,

Come to think of it, I did replace the fuel filter 6 to 12 months
before this stalling began. I'm no where near a mechanic so anything
is possible although I was careful to put the filter flow in the
correct direction. The pump does whine a bit but I can't say for sure
if it has gotten louder. I'm not sure if he did a fuel pressure test
or check the fuel pressure regulator.

The cold start valve IIRC is located where? And the fuse is
located where? I'll check the fuel filter and see if the gas cap
technique helps out. I really appreciate your input on this.

[youngc]

Tony,

Thanks for your suggestion. The fuel pump intake screen is
located where? On or inside the pump? The pump is directly hooked up
to the fuel filter then going to the gas tank. What is the job of the
fuel pump relay? Just curious.

Many thanks,

Chris

[youngc]

Dave,
To respond to your first question: no, it doesn't immediately start
back up after stalling. I need to wait a good 45 minutes to get it
going again, usually. The stalling symptoms usually appear immediately
after I start the car back up after a 45 minute period. If the car
sits about 12 to day it will start back up and drive but the symptoms
will appear in the 5-10 minute range.

Thanks,
Chris

[youngc]

cp,

Thanks. He is a bit hard to communicate with but I will prevail.

--Chris

[Tony]

If it is like the Type 44s in that time the fuel pump is located in the bottom
of the fuel tank and is surrounded with a mesh screen to filter the fuel before
it enters the pump. If the tank is shedding its inner lining the bits coat the
screen and impede flow to the pump. Correction requires opening the tank and
removing the pump to cut off the screen. Really not too bad of a job if a bit
messy. If you aren't into DIY a local independent audi mechanic could handle it
easily.

Fuel pump relay turns power on to the pump when the engine is running and in
some cases when the ignition switch is turned to the 'on' position. If the
computer sees the engine stop running it tells the relay to stop pumping fuel.
This is a safety feature for possible accident situations. Relay is likely to be
located in the main relay box that is probably under the hood.

youngc wrote:

[cp]

[dave AKA vwdoc1]

The fuel filter should be after the fuel pump. The part I am referring to
is a plastic 'reservoir' (for lack of what it is truly called) and is before
the fuel pump or between the tank and the pump. Maybe yours doesn't have it
but if it does maybe it is clogged up some.

Fuse is located in a bank of fuses towards the left side of the fuse box.
The fuses are all in a row and can look like "spare" fuses. If you take
them out you will see that some of them actually have terminals for the
fuses, but some won't. ;-)

The cold start valve is located on the intake manifold and will have a
braided fuel line coming from the fuel distributor going to it. Sometimes
the grounding wires there vibrate and break leading to a problem with the
fuel pressure regulator.

later,
dave
(One out of many daves)



"youngc" <youngc123@hotmail.com> wrote in message
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