'86 5K TQ don't want to start after air and fuel filter change

Hi,

My '86 5K TQ don't want to start after an air and fuel filter change. I did get it started twice by cranking but as soon as it
starts up it will die if I don't hold the gas. It drives great but dies upon attempting to idle. It starts no problem when the car
is moving and is put in gear. What could be the problem? Could it be air in the system? What is the fuel filter change procedure,
does the system have to be bled afterwards? Also, before I touched the car today, when turning off the car when the engine is warm,
the car won't start again for 5-8 minutes, after that it starts no problem. Though it never has any problems starting when the car
is moving and is put in gear. Cold starts are immediate, though not anymore of course.

Thank you in advance for any help!
cp

It sounds like you have a vacuum leak.

Or, you may have disconnected the wires to the throttle body for the switch that
controls the ISV.

No special bleeding procedure for filter changes.

Tony
Current: 98.5 A4 1.8TQM
Previous: four T44s '84 - '91

cp wrote:
> Hi,
>
> My '86 5K TQ don't want to start after an air and fuel filter change. I did get it started twice by cranking but as soon as it
> starts up it will die if I don't hold the gas. It drives great but dies upon attempting to idle. It starts no problem when the car
> is moving and is put in gear. What could be the problem? Could it be air in the system? What is the fuel filter change procedure,
> does the system have to be bled afterwards? Also, before I touched the car today, when turning off the car when the engine is warm,
> the car won't start again for 5-8 minutes, after that it starts no problem. Though it never has any problems starting when the car
> is moving and is put in gear. Cold starts are immediate, though not anymore of course.
>
> Thank you in advance for any help!
> cp
>
>

> It sounds like you have a vacuum leak.

Vacuum leak? Are there any other tell-tale symptoms I should look for? Today, after getting back from a trip (in another car) I went
to start it up after letting it sit for a couple of days and it started right up, idled fine and the problem started again a couple
of minutes later.

> Or, you may have disconnected the wires to the throttle body for the switch that controls the ISV.

You know, I might have nudged something. Will take a look at the factory manual what it could be.

Thank you!

cp

Here's a Q&D vacuum leak test:

- engine idling
- remove oil dipstick
- engine should stumble and run poorly. Replace dipstick.
- open oil filler cap
- engine should die

If these conditions do not occur you have a vacuum leak that is either
intermittent or being compensated for by other adjustments and needs to be
coppected.

Damn, these Audi's are so much fun :-)

cp wrote:
>>It sounds like you have a vacuum leak.
>
>
> Vacuum leak? Are there any other tell-tale symptoms I should look for? Today, after getting back from a trip (in another car) I went
> to start it up after letting it sit for a couple of days and it started right up, idled fine and the problem started again a couple
> of minutes later.
>
>
>>Or, you may have disconnected the wires to the throttle body for the switch that controls the ISV.
>
>
> You know, I might have nudged something. Will take a look at the factory manual what it could be.
>
> Thank you!
>
> cp
>
>

> Here's a Q&D vacuum leak test:
>
> - engine idling
> - remove oil dipstick
> - engine should stumble and run poorly. Replace dipstick.
> - open oil filler cap
> - engine should die
>
> If these conditions do not occur you have a vacuum leak that is either intermittent or being compensated for by other adjustments
> and needs to be coppected.
>
> Damn, these Audi's are so much fun :-)

Ah, so this is normal, I was wondering why the car would die when the oil filler cap was removed.

My mechanic friend however checked it out and said that the fuel pump is bad, says fuel stops coming from the (losened) fuel filter
connection before the car dies, ahhhhhhhhh I don't want to waste money on this!! What's a good place to get a fuel pump assembly?
Here in Canada the fuel pickup, fuel pump and wire harness costs about $350USD, can't I just get the fuel pump?

cp

Shokan usually has a $125 US fuel pump special on ebay. The pump is Pierburg and
is good. I used one in a '91 100qm. Quiet and works. What more can one ask for.

Shokan increases the price if you order on the phone. Gotta use ebay. Not sure
how that would work shipping to Canada.

cp wrote:
>>Here's a Q&D vacuum leak test:
>>
>>- engine idling
>>- remove oil dipstick
>>- engine should stumble and run poorly. Replace dipstick.
>>- open oil filler cap
>>- engine should die
>>
>>If these conditions do not occur you have a vacuum leak that is either intermittent or being compensated for by other adjustments
>>and needs to be coppected.
>>
>>Damn, these Audi's are so much fun :-)
>
>
> Ah, so this is normal, I was wondering why the car would die when the oil filler cap was removed.
>
> My mechanic friend however checked it out and said that the fuel pump is bad, says fuel stops coming from the (losened) fuel filter
> connection before the car dies, ahhhhhhhhh I don't want to waste money on this!! What's a good place to get a fuel pump assembly?
> Here in Canada the fuel pickup, fuel pump and wire harness costs about $350USD, can't I just get the fuel pump?
>
> cp
>
>

hmmmmmm but don't I need the whole assembly with it? (fuel pick up and wires)

cp

> Shokan usually has a $125 US fuel pump special on ebay. The pump is Pierburg and is good. I used one in a '91 100qm. Quiet and
> works. What more can one ask for.
>
> Shokan increases the price if you order on the phone. Gotta use ebay. Not sure how that would work shipping to Canada.
>
> cp wrote:
>>>Here's a Q&D vacuum leak test:
>>>
>>>- engine idling
>>>- remove oil dipstick
>>>- engine should stumble and run poorly. Replace dipstick.
>>>- open oil filler cap
>>>- engine should die
>>>
>>>If these conditions do not occur you have a vacuum leak that is either intermittent or being compensated for by other adjustments
>>>and needs to be coppected.
>>>
>>>Damn, these Audi's are so much fun :-)
>>
>>
>> Ah, so this is normal, I was wondering why the car would die when the oil filler cap was removed.
>>
>> My mechanic friend however checked it out and said that the fuel pump is bad, says fuel stops coming from the (losened) fuel
>> filter connection before the car dies, ahhhhhhhhh I don't want to waste money on this!! What's a good place to get a fuel pump
>> assembly? Here in Canada the fuel pickup, fuel pump and wire harness costs about $350USD, can't I just get the fuel pump?
>>
>> cp

cp,
No, you just need the pump. The wires just bolt on. There's lots written
up on Audifans and (probably) Audiworld about replacing the pump - most
important thing, aside from the warnings about gas fumes being
dangerous/explosive/etc.etc. is that you make sure that the orientation of
the connections to the pump remain unchanged - otherwise your gas gauge will
stop reading when the float arm hangs up on the wires/hose. BTDT numerous
times - I gave up.
Cheers!
Steve Sears
1987 Audi 5kTQ - fuel gauge won't read the last 1/8th of a tank
1980 Audi 5k
1962 and '64 Auto Union DKW Junior deLuxes
(SPAM Blocker NOTE: Remove SHOES to reply)
"cp" > wrote in message
news:quaUe.166626$wr.119945@clgrps12...
> hmmmmmm but don't I need the whole assembly with it? (fuel pick up and
wires)
>
> cp
>
> > Shokan usually has a $125 US fuel pump special on ebay. The pump is
Pierburg and is good. I used one in a '91 100qm. Quiet and
> > works. What more can one ask for.
> >
> > Shokan increases the price if you order on the phone. Gotta use ebay.
Not sure how that would work shipping to Canada.
> >
> > cp wrote:
> >>>Here's a Q&D vacuum leak test:
> >>>
> >>>- engine idling
> >>>- remove oil dipstick
> >>>- engine should stumble and run poorly. Replace dipstick.
> >>>- open oil filler cap
> >>>- engine should die
> >>>
> >>>If these conditions do not occur you have a vacuum leak that is either
intermittent or being compensated for by other adjustments
> >>>and needs to be coppected.
> >>>
> >>>Damn, these Audi's are so much fun :-)
> >>
> >>
> >> Ah, so this is normal, I was wondering why the car would die when the
oil filler cap was removed.
> >>
> >> My mechanic friend however checked it out and said that the fuel pump
is bad, says fuel stops coming from the (losened) fuel
> >> filter connection before the car dies, ahhhhhhhhh I don't want to waste
money on this!! What's a good place to get a fuel pump
> >> assembly? Here in Canada the fuel pickup, fuel pump and wire harness
costs about $350USD, can't I just get the fuel pump?
> >>
> >> cp
>
>

Hi Steve!

Always good to hear from you!

Well, my mechanic friend took a look at the car today and says that the fuel pump works fine. He took off the fuel pressure
accumulator and a load of RUST came out (why is a "fuel pressure accumulator" needed?? (Couldn't they build up fuel pressure by
activating the fuel pump before ignition?). Should I flush out the gas tank? Supposedly, if the "fuel pressure accumulator" was the
problem then I would have trouble starting the car up after it's been sitting over night, but the car starts fine, idles OK for a
couple of minutes and then dies. And THEN I have trouble starting it, though it starts no problem when thrown into gear when the car
is moving. Any idear what this could be?

Thank you!

cp


> cp,
> No, you just need the pump. The wires just bolt on. There's lots written
> up on Audifans and (probably) Audiworld about replacing the pump - most
> important thing, aside from the warnings about gas fumes being
> dangerous/explosive/etc.etc. is that you make sure that the orientation of
> the connections to the pump remain unchanged - otherwise your gas gauge will
> stop reading when the float arm hangs up on the wires/hose. BTDT numerous
> times - I gave up.
> Cheers!
> Steve Sears
> 1987 Audi 5kTQ - fuel gauge won't read the last 1/8th of a tank
> 1980 Audi 5k
> 1962 and '64 Auto Union DKW Junior deLuxes
> (SPAM Blocker NOTE: Remove SHOES to reply)

Sounds like you have a problem with the coating on the inside of the fuel tank
falling off and clogging the fuel pump's intake screen. Common problem for pre
'90 T44s

Check history on Audiworld T44 forum for correction:
http://forums.audiworld.com/v8/

The recommended Audi fix is to cut off the intake screen from the fuel pump and
then replace the fuel filter.

cp wrote:
> Hi Steve!
>
> Always good to hear from you!
>
> Well, my mechanic friend took a look at the car today and says that the fuel pump works fine. He took off the fuel pressure
> accumulator and a load of RUST came out (why is a "fuel pressure accumulator" needed?? (Couldn't they build up fuel pressure by
> activating the fuel pump before ignition?). Should I flush out the gas tank? Supposedly, if the "fuel pressure accumulator" was the
> problem then I would have trouble starting the car up after it's been sitting over night, but the car starts fine, idles OK for a
> couple of minutes and then dies. And THEN I have trouble starting it, though it starts no problem when thrown into gear when the car
> is moving. Any idear what this could be?
>
> Thank you!
>
> cp
>
>
>
>>cp,
>>No, you just need the pump. The wires just bolt on. There's lots written
>>up on Audifans and (probably) Audiworld about replacing the pump - most
>>important thing, aside from the warnings about gas fumes being
>>dangerous/explosive/etc.etc. is that you make sure that the orientation of
>>the connections to the pump remain unchanged - otherwise your gas gauge will
>>stop reading when the float arm hangs up on the wires/hose. BTDT numerous
>>times - I gave up.
>>Cheers!
>>Steve Sears
>>1987 Audi 5kTQ - fuel gauge won't read the last 1/8th of a tank
>>1980 Audi 5k
>>1962 and '64 Auto Union DKW Junior deLuxes
>>(SPAM Blocker NOTE: Remove SHOES to reply)
>
>
>