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Old February 5th 07, 09:19 PM posted to alt.autos.audi
TonyJ
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Posts: 80
Default '87 Audi 4000s fuel problem - wont start



wrote:
> On Feb 5, 8:41 am, "dave AKA vwdoc1" > wrote:
>
>>hmmm
>>Not to get too picky or exact, but did you perform the tests like I
>>instructed? :-)
>>Cranking the engine brings other things that could cause problems such as
>>the ign switch which could, if faulty, lose power to key components like the
>>FPR, fuel pump, ign system, etc! Even the power could drop below 10 volts
>>while you are cranking over the engine.
>>
>>It sounds like you disconnected the lines to the injectors instead of
>>removing the injectors.
>>It sounds like you did not jump the fuel pump relay.
>>
>>Now if you are getting correct power to the fuel system and ign system, and
>>you have fuel pressure at the fuel distributor, and you pull up on the fuel
>>distributor plate while the fuel pump is running and you get no fuel out of
>>the injectors................................then it sounds like either the
>>FPR or the Fuel Distributor might be the cause of your problem. But I am
>>just guessing here since I am not sure if power gets lost to the FPR while
>>you are cranking over the engine.
>>
>>Bentley is the better manual and you can find them on Ebay sometimes.
>>
>>later,
>>dave
>>(One out of many daves)
>>
> wrote in message
>>
groups.com...
>>
>>
>>
>>
>>>On Feb 4, 6:13 pm, "dave AKA vwdoc1" > wrote:
>>>
>>>>Do you have a repair manual? Even a Haynes (cough cough) could help
>>>>some.

>>
>>>>Remove intake boot off of fuel distributor so you can manually lift up
>>>>the
>>>>plate.
>>>>Remove injector(s) out of the cylinder head and aim into a container so
>>>>you
>>>>can examine spray pattern.
>>>>Remove fuel pump and jump correct wires to run fuel pump continually.
>>>>Turn ign on but do not start car.

>>
>>>>Pull up on fuel distributor plate to check fuel injector spray pattern.
>>>>Tell us what happens?
>>>>If it sprays out that is good and you might just need to adjust something
>>>>or
>>>>change a sensor.
>>>>If nothing sprays out then I suspect either a bad fuel distributor, bad
>>>>Fuel
>>>>Pressure Regulator, bad wiring, missing fuse, clogged injectors, no fuel
>>>>pressure or ????

>>
>>>>The ground wire for the FPR usually breaks at the cold start valve.

>>
>>>>No the temperature sensor for the gauge is different than the one for the
>>>>fuel injection. ;-)

>>
>>>>later,
>>>>dave
>>>>(One out of many daves)

>>
> wrote in message

>>
legroups.com...

>>
>>>>>Hello Audi 4000 fuel help still needed

>>
>>>>>Been busy at work, not much time to work on the Audi until last week.

>>
>>>>>Still having problems getting this car to run, was wondering if there
>>>>>are any other ideas out there?

>>
>>>>>I still can not get the fuel injector unit to shoot fuel into the
>>>>>injectors. It still fires fuel to the cold start valve, enough juice
>>>>>to run 3-5 seconds.

>>
>>>>>I checked all fuses, put new ones in the blank spaces.

>>
>>>>>I checked the fuel injector air-door, it opened fine.

>>
>>>>>I replaced the entire fuel injector unit with a used one I had from a
>>>>>parts lot I bought.

>>
>>>>>I changed the fuel regulator as well, the one on the injector unit, I
>>>>>believe this is the "Differential fuel pressure sensor (just in
>>>>>front of fuel distributor." ,that you mentioned
>>>>>As far as the "Failing engine temp senso" " the MFTS ", is this the
>>>>>same as the temperature sending switch? . Could this really keep the
>>>>>fuel injector unit from firing? Can I bypass this to test it?
>>>>>There is no massive air leak at the large intake manifold
>>>>>The ignition switch is fine, it is new, it is getting power to the
>>>>>fuel pump and other systems

>>
>>>>>Any help would be appreciated!!

>>
>>>>>Richy Jackson
>>>>>On Jan 2, 11:07 pm, "dave AKA vwdoc1" > wrote:
>>>>>
>>>>>>Like TonyJ said..............it might be a Failing engine coolant temp
>>>>>>sensor (CTS)

>>
>>>>>>Or a fuse in the fuse box. It is positioned to look like a spare fuse
>>>>>>and
>>>>>>many times I will find it missing on a vehicle that is not running
>>>>>>right
>>>>>>if
>>>>>>running at all. 8^o
>>>>>>Examine all of the fuses for any broken ones and stick a fuse in all
>>>>>>sockets
>>>>>>with terminals.

>>
>>>>>>Or it could be the ground wire for the fuel pressure regulator is
>>>>>>broken
>>>>>>and
>>>>>>it should be located at the cold start valve.

>>
>>>>>>Or it could be a defective fuel distributor.

>>
>>>>>>Or it could be a massive air leak at the large intake manifold boots.
>>>>>>Maybe
>>>>>>a light engine backfire into the intake system along with the gas
>>>>>>pedal
>>>>>>being depressed might have caused a hose/pipe to pop off creating a
>>>>>>large
>>>>>>vacuum leak.

>>
>>>>>>Or it could be the ign switch not allowing power to the systems when
>>>>>>it
>>>>>>is
>>>>>>in the ON position. Telltale signs would be those red idiot lights
>>>>>>not
>>>>>>being ON with the ign ON or while cranking over the engine.

>>
>>>>>>good luck and let us know what happens!
>>>>>>later,
>>>>>>dave
>>>>>>AKA vwdoc1

>>
>>>>>>"TonyJ" > wrote in message

>>
...

>>
wrote:
>>>>>>>
>>>>>>>>I was wondering of anyone could help me with a problem that
>>>>>>>>suddenly
>>>>>>>>developed with my AUDI,

>>
>>>>>>>>The car is a 1987 Audi 4000s 1.8L
>>>>>>>>Here is the deal, the car will start for second or two, but will
>>>>>>>>not
>>>>>>>>rev up, then it dies.

>>
>>>>>>>>Fuel pump and filters are new.

>>
>>>>>>>>Strong fuel pressure to the Fuel injector unit.

>>
>>>>>>>>The injector unit is sending fuel to the cold start valve, but not
>>>>>>>>to
>>>>>>>>the cylinders, thus the car will start but will not continue to
>>>>>>>>run.
>>>>>>>>The pressure to the cold start valve is strong, but not a drop to
>>>>>>>>the
>>>>>>>>fuel injectors.

>>
>>>>>>>>I replaced the external fuel regulator with a spare one and checked
>>>>>>>>for
>>>>>>>>vacuum leaks etc.

>>
>>>>>>>>I am not sure where to look from here, internally on the Fuel
>>>>>>>>Injection
>>>>>>>>Unit, or to a relay or other control.

>>
>>>>>>>>As I stated the problem happened overnight.

>>
>>>>>>>>Any help would be appreciated.
>>>>>>>>I have not used a internet group before, do I hope I am doing this
>>>>>>>>right...........

>>
>>>>>>>>Thanks,

>>
>>>>>>>>Richy Jackson

>>
>>>>>>>If the air plate just above the air filter is stuck the injectors
>>>>>>>will
>>>>>>>not
>>>>>>>fire. This can be due to vacuum leaks (you checked but check
>>>>>>>again)
>>>>>>>or
>>>>>>>deposits on the rod above the plate.

>>
>>>>>>>Open air cleaner and reach up into the intake just above. The plate
>>>>>>>should
>>>>>>>move but with a little pressure. Don't force it.

>>
>>>>>>>Other ideas:
>>>>>>>Differential fuel pressure sensor (just in front of fuel
>>>>>>>distributor.

>>
>>>>>>>Blown engine management fuse (in the side of the relay box.

>>
>>>>>>>Failing engine temp sensor. In the T44s it is called the MFTS and it
>>>>>>>is
>>>>>>>located by the upper radiator hose inlet to the engine.- Hide quoted
>>>>>>>text -

>>
>>>>>>- Show quoted text -- Hide quoted text -

>>
>>>>- Show quoted text -

>>
>>>Hey Dave,

>>
>>>Thanks for the reply,

>>
>>>Yup, I have a good old Haynes manual; read it a couple times...!! I will
>>>get a shop manual..

>>
>>>I did take off the hoses to the fuel injectors and cranked the engine,
>>>nothing comes out, except for the line to the Cold Star Valve that
>>>gives a nice spray to the intake...

>>
>>>I tested this with both my original, and a replacement fuel injector
>>>unit, in both cases, plenty of fuel to cold start valve, nothing to
>>>fuel injectors. I already pulled the plate up as you suggest. still
>>>nothing from the fuel injector hoses

>>
>>>Replaced both fuel regulators, car has new fuel pump and filters,
>>>plenty of fuel pressure to injector unit...

>>
>>>The ground to the cold start valve is fine

>>
>>>As I have tried a replacement injector unit, it does the same thing, I
>>>am thinking it I electrical, fuses are good.

>>
>>>I read the voltage of the fuel regulator that is on the fuel
>>>distributor unit or, it shows 8 v, there is an electrical connection
>>>on the other side.

>>
>>>Something is keeping the Fuel distributor unit from shooting fuel to
>>>the injectors, any other thoughts?

>>
>>>Tell me again about the temp sensor for the fuel distributor, where is
>>>it located & would it stop the fuel injector unit from firing?

>>
>>>This car ran fine until a couple months ago, I changed brake lines &
>>>complete exhaust & then it stopped running...

>>
>>>Any help would be cool..

>>
>>>Richy Jackson- Hide quoted text -

>>
>>- Show quoted text -

>
>
> Thanks Dave
>
>
> Sorry, I was not disrepecting your instructions.....I had run the
> tests the way I stated a couple days ago before I read
> yourinstructions...
>
> I will dig in & get the Bently manual
>
> If I could bother you with one more Q... tell me about how to jump the
> fuel punp relay, did you mean the pump itself, I did this acouple
> timnes when I tested, how do I jump the FPR?
>
> Thanks
>
> RJ
>

Not to get in the middle of you and Dave but, Dave is referring to placing a
fuse in the top of the fuel pump relay to 'jump' the pump to running. This is a
manual override. Some models may not have the fuse slot on the top of the relay
so if this is the case you could use a jumper wire in the slots of the relay if
you pull it out. Careful, as you know sparks / fuel are dangerous.

One other thought is that some people have traced a no start condition on the
T44s to a sticking decel valve located in the passenger finder and hidden behind
the fuel distributor. when the stick they create a vacuum leak. I don't know if
you even have one on the 4000 and I think that lifting the air plate would have
overridden this issue but thought it was worth suggesting.

Good luck. Dave's the authority.
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