Conference terri::cars_uk

I think the Audi has a smiliar setup to my VW.   Look to check the 6th 
injector, bolted into the inlet manifold (not the engine, as the 5 are to 
each cylinder).


This should be injecting petrol as the engine is cranked on the starter 
motor, for up-to 5 seconds.  This is to provide a rich mixture for cold 
starting.   It does not inject after 5 seconds, or if the starter key is 
released or if the engine is already warm.

It's probably best to get a hyanes manual for the best fault finding 
procedure to see if these parts are really at fault.

I would expect the thermo-time sender to cost about �40 and the auxilliary 
fuel-injector to cost about �80, at these prices it may be worth visiting a 
breakers.

Rob.

    Back in 1984, my Audi 80 Quattro, 5 cyl, 136 bhp had exactly the same
    problem.
    
    Audi told me this was normal (5 sec) and was due to anti-pollution
    settings, etc ...

1989 Audi 90 (5 Cylinder, 1986 cc - Fuel injected), has been
running fine until recently. The main problem is that the 
performance has gradually got worse over the last month or so. If 
driven slowly its OK but once you put the boot down it appears to 
flood the engine so it splutters /stalls and eventually picks up.
The problem is worst from cold start and gets better as the engine 
warms up, but even when warm still not giving the power it should.

My mechanic reckons its a result of my using leaded petrol over the
last year. He reckons that the injectors have got dirty and hence 
the problem. This mechanic is not an Audi expert and it was he who 
advised that I use leaded petrol.

Any comments?

Gerry Conway @ILO
822-4833

    
    Why not try a can of the injector cleaning fluid, I know that Porsche
    use it on older cars.

    Re. 'leaded/unleaded'
    
    I hadn't heard any particular claims before stating that unleaded
    petrol was less likely than leaded to block injectors.
    
    The injectors on my Alfa became badly blocked after more than 100,000
    miles.  That was with leaded fuel, due to the age of the car, but I
    didn't think the 'lead' had anything to do with it.
    
    For the last year, I have been using Shell petrol for almost all my
    fill-ups, as their is a Shell petrol station in a convenient position
    on my route to work.  Certainly goes to show that their bull in the
    adverts isn't right - it didn't clean the internals of my engine !
    The blocked injector did result in a severely burnt valve though.
    Whatever, I don't use Shell petrol now - probably nothing to do
    with their fuel, but I do know about problems with 'Formula Shell'
    when that first came out (I didn't use it then).
    
�    Why not try a can of the injector cleaning fluid,
    
    I tried this on my car - probably too late - but it had no effect.
    
�                             -< Or new injectors? >-
    
    You can get injectors 'ultrasonically cleaned'.  There's an article
    on this in this month's CCC magazine (in the UK).
    
    J.R.

.3> 	My mechanic reckons its a result of my using leaded petrol 
    
.3>	This mechanic is not an Audi expert and it was he who 
.3>	advised that I use leaded petrol.
    
    My advice is to change your mechanic ! He can't even give consistent
    advice, so he was wrong at least once.
    
    Terry :-)
    

I know this note has been quiet for a long time, but...

I have the same problems described above. I took the car (Audi 
90) to a Bosch fuel injection specialist who told me Bosch had 
released an updated cold start injector to cure this problem. It 
didn't, but it did cost me >�100 to find out :-(

As well as not starting quickly, once it does start there's a 
cloud of blue smoke and a smell of petrol too. The car does not 
smoke once running normally and only has 54,000 miles on the 
clock. Once running, the engine is fine _until_ it just starts 
to warm up, whereupon it mis-fires if given a boot-full and is 
generally sluggish. However, as soon as it has heated up a 
little more, it behaves wonderfully.

Even with these problems, it is undoubtedly the best car I have 
owned (I've owned a few...). However, I would really like to fix 
the start/miss problems. Any constructive suggestions as to what 
the problems might be would be VERY gratefully received!!

Keith.

    Faulty sender/sensor somewhere
    
    Injector problem (doubt this from what you say, have you had new ones
    fitted? Try some sort of fuel injector cleaning).
    
    The smoke must be oil burning, probably valve seals...... ?

  Rip out the f/i system and install a Weber.....  At least that is what I
  did on our '85 Jetta (1.8 ltr).  Cost me $400 for the whole kit which was
  about the cost of disgnosing the f/i system, not counting actually
  replacing any parts.
  
  Of course, your local emissions testing shop might not like the
  conversion, but it does sound a whole lot better! :-)
  
  Dave

Thanks for the fast replies...

re: .8 

I had the injectors cleaned and inspected (they're OK) and I've 
tried to keep them clean with petrol additives. Having said 
that, the Audi does seem to get through plugs quite quickly.

Each thing I try seems to make a small improvement, but never a 
complete fix... Now, the faulty sender/sensor... this had 
occured to me too. I also wondered about the engine management 
system? In days of yore, I used to troubleshoot my car 
electrics. Not today. More wires and chips than an AXP... 

The car also has a trivial (but annoying) problem in that the 
water temperature guage only works 20% of the time. I asked my 
local garage to take a look, but of course, it was with them 
during the 20% up-time. Now, I *could* try to get a real expert 
to take a look. Then again, I could just live with the problems 
and retire early on the money I save ;-)

re: .9

Years ago, I used to dream of putting a pair of twin-choke 
Webber DHOC(?) 48 carbs on a Triumph Dolomite Sprint I had. I 
made all the plans: how to get it (safely) up to around 180bhp, 
0-60 <6 seconds, 120mph+, cornering and brakes to match. Problem 
was, I didn't have the money! Now, well, I like the Audi. 
However, if I thought it would cure the problem, I might just be 
tempted...

Keith.

    If you've got the engine I'm thinking of, you'd have problem fitting
    twin DCOE Weber's onto 5 cylinders ;-)
    
    Sensor/engine management .... could be to blame. Take it to any decent
    tuning place (is your injection system a BOSCH one?) and they should be
    able to run diagnostics on it.
    
    If they say you need a new ECU, try one of the many 'chip'
    manufacturers, sometimes a new upgraded chip can cure this little
    problems..... hopefully they'll let you try out the new chip first
    and, if it fixes the problem, you pay your money and leave!
    
    I don't suppose there's any chance that the temperature sender is
    shared by the dial AND the ECU, is there? Do the two problems correlate
    (ie. when the dial doesn't work the engine is dodgy, and vice versa). I
    would doubt this but.....
    
    Have fun!
    
    Dan

There may be some problems with your plan to fit Webers if the the car has a catalytic
convertor - you will probably ruin the cat! You may also have problems with the MOT 
emissions tests for CO content.

Does this car have the Bosche electo-mechanical injection system (Jetronic 
something-or-the-other). If so I had a similar problem with such a system. In my case the 
cold-start injector was replaced in an attempt to cure cold start problems, and like yours 
it had no effect. A little investigation revealed that the cold start injector is controlled 
by a bi-metalic timer/sensor, this was replaced (about #15) and all was sweetness and light!

I had similar clouds of blue smoke when the fault was present which was cured when the cold 
start sensor was replaced. I suspect this is due to lubricant being flushed out of the 
cylinders by excessive fuel.

If this is the electro-mechanical system I would also advise you to get the (mechanical) 
mass volume measurement device set up by a reputable Bosche agent, it's pretty quick and 
simple if they know what they are doing and have the right equipment.

- John.

    There may be some problems with your plan to fit Webers if the the car
    has a catalytic convertor - you will probably ruin the cat! You may
    also have problems with the MOT  emissions tests for CO content.

    Does this car have the Bosche electo-mechanical injection system
    (Jetronic  something-or-the-other). If so I had a similar problem with
    such a system. In my case the  cold-start injector was replaced in an
    attempt to cure cold start problems, and like yours  it had no effect.
    A little investigation revealed that the cold start injector is
    controlled  by a bi-metalic timer/sensor, this was replaced (about #15)
    and all was sweetness and light!

    I had similar clouds of blue smoke when the fault was present which was
    cured when the cold  start sensor was replaced. I suspect this is due
    to lubricant being flushed out of the  cylinders by excessive fuel.

    If this is the electro-mechanical system I would also advise you to get
    the (mechanical)  mass volume measurement device set up by a reputable
    Bosche agent, it's pretty quick and  simple if they know what they are
    doing and have the right equipment.

- John.


    

    Forget about carbs for road cars those days.

RE:13

Sorry, wrote .12 on NetNotes for Windows NT :-}

re: .last_few

I have already forgotten about carbs - although I love the idea 
of multiple twin choke Webbers, it's not really a goer on a 5 
cylinder Audi. I should maybe also mention this is an older Audi 
and must have leaded fuel, which is a shame. I won't buy a 
leaded only next time, but I have to confess that it didn't dawn 
on me to ask, I assumed it would run unleaded (I know, don't 
assume: it makes an ASS of yoU and ME :-)

I was quite taken with the idea of re-chipping as a potential 
solution to the poor performance during the warm-up period. 
Could you maybe post some pointer to reputable traders (or maybe 
pointers to other notes)? I'd really appreciate it. (searching 
this conference takes a lonngggg time!!)

I'm also _very_ interested with the suggestion to look at the 
cold start sensor - thank very much indeed, John, I shall make 
investigations ASAP. Certainly, all the symptoms bear out (smoke 
only on startup, smell of petrol etc). Yes, this will definitely 
be my first port of call!

Thanks to everyone who has helped so far - I'll keep you posted.

Keith.

I've checked with the local VW parts pusher and the only
sensor they can find is a Thermo-Time Switch which is located
in one end of the cylinder block. Of course, if "Sir cares to
leave the car with them overnight, they'll see what they can
do." As the car was with them 3 times under warranty for this
problem, I doubt they will fix it this time. If, on the other
hand,  they were to fix it, I'd be well fed up that they
didn't cure it the first time!!

Anyway, does this sound like the gadget I need to replace?
I'm asking as it costs �56 + VAT and I've already invested
far too much on this problem to no avail...

Thanks for the help and suggestions so far,

Keith.

Yup, that sounds like the gizmo. It's normally bolted to the cylinder 
block so that it soaks engine heat to prevent it operating during a 
warm engine start. When the engine is cold an internal heater element 
heats the bi-metallic strip contact which normally opens the switch 
after about 4-10 seconds. This is long enough to supply extra fuel 
via the cold start injector to get the engine firing - the normal 
injection mixture control then takes over adjusting itself for the 
current engine temperature/air temperature.

There is one more bit of trickery involve in all this - it is the 
'pulse-relay'. To prevent the thermo time-switch heater coming on as 
soon as the ignition is switched on (bad news if you are slow hitting 
the starter) this special relay supplies the heater - the relay is 
only called when the engine is cranking (it detects ignition pulses). 

I would check it was sort of working by removing the cold start 
injector from the plenum chamber and holding it inside a jam jar 
while an accomplice cranked the (cold) engine for 10-15 seconds. You 
should see a healthy spray of petrol which should stop before the 15 
seconds of cranking finishes. If that looked OK I would put it all 
back together, start the engine and get it hot and then disconnect 
the electrical connection to the cold start injector and go for a 
drive to see if appeared OK with it disabled (which it should be 
anyway).

Please don't blame me if this all turns out to be a red herring :-}
To be on the safe side take the car to an injection specialist (it 
sounds like exactly the same system as used in VW Golf GTi's, SAAB's, 
Volvos, etc. of the vintage of your car).

- John.

BTW - your remark re chipping doesn't apply here, there's no chips to 
chip!!!. These systems are purely electo-mechanical - the good news 
is that you'll never have to fork out for a 'new ECU Sir' at 500 
quid!

re: .18

I think I'll try your suggestions before putting my hand in
my pocket and buying a new sensor. I am extremely wary of
using the services of "experts" as to date, I haven't had
much luck with them. I used to do all my own servicing in the
days when I had time, energy and knowledge for such things.
Engines today seem a bit too complicated - or maybe I'm
getting lazy. Now I have the cars serviced and repaired by a
local chap who is definitly a generalist and I suspect the
minutae of problems like this simply aren't worth him
learning! For the vast majority of work however, he's ace.

What I think I'll try to help isolate the problem is simply
disconnecting the sensor when the engine is cold and see what
effect that has. If its totally broken, the effect should be
nothing! Thereafter I can move onto removing the cold-start
injector and your other suggestions. One question: the
pulse-relay; do you know if that is part of the sensor
package or a separate item? If the latter, I can remove it
from the game also to see what effect it has.

Finally, given this is a totally electro-mechanical system
with no electronic engine management system, does the hiccup
in performance when the engine is slightly warm indicate that
maybe the injection system and the engine have a minor
compatibility problem?

Keith.

The pulse relay is normally buried somewhere behind the dashboard or 
some other equally inaccessible place. You can't simply remove it 
because it serves other functions (like control of a cut-off valve 
and the the high-pressure fuel pump).

If you run the car with the electrical connection to the cold-start 
injector removed and you continue to get running problems (and we can 
assume the the cold-start injector is not leaking since you bought a 
new one - hah,hah,hah) then you have other problems. This could be in 
the metering unit, coolant sensor, air temperature sensor or the 
high-pressure delivery side of the system. At this point you really 
need a specialist to look at it (I keep hinting!!!).

Look on the bright side, these systems are normally mega-reliable and 
far cheaper to fix than the current ECU mico-processor controlled 
systems - they also drive better.

- John.

BTW - if your system has a high pressure fuel filter -- when was the 
last time it was replaced?

OK, thanks. I'm starting to get the hint ;-)

I'll still try the crude tests I'd planned, but maybe I'd
better search this conference for recommended "experts".

Oh yes, the fuel filter was changed last week... honest!

Keith.

Last weekend I had the chance to try out my simple tests (I can only try one
test a day as I need a cold morning start for each attempt...).

Anyway, I disconnected the wires to the cold start injector as I reasoned that
it wasn't going to work if it didn't get any instructions ;-) I couldn't really
detect any change in starting performance. This was a mild surprise as I had
expected some change.

Next day I removed the wiring from the temperature sensor (having replaced the
cold start wiring). Guess what? It started more easily... at a guess, about half
as long as with the wiring connected. Of course, I didn't believe it; some fluke
or another. So I left the harness disconnected and I have to say that it really
does appear to be starting better; not well, but better. Question: am I doing
any harm by leaving the sensor disconnected? If my understanding is correct,
this gadget is only involved with cold start, so I *think* I'm OK, but I thought
I'd better check.

Now if only I can find a garage that'll be prepared to sell me a sensor on a fix
or return basis... ;-)

Keith.

    	It appears to me that your tests showed either:
    
    	1) The cold Start injector needs to be replaced as it is either
           fouled (sp) or inoperative (because there was not any change when
    disconnected).
    	2) The sensor might break the circuit when warm so by
    disconnecting the sensor you make the engine do a "warm start" which
    should also modifiy the injection timing (cold vs warm) and duration.
    
    	Just a thought.

Thanks for the continued input - all help and/or insights are very much
appreciated.

re: .23 - I hope the injector is not blocked or duff - I recently spent >�100
having the Bosch replacement fitted - the one that's supposed to cure this
problem :-(

I was/am slightly concerned by leaving the wiring disconnected in case I'm
encouraging the injection system to run rich (i.e. it's not receiving a "you're
warm now" message). However, the starting is definitely improved, but not the
performance when slightly warm, that's the same. Also, the temperature guage
hasn't worked since I disconnected the cold start sensor. Again, that could be
concindence given its history, but maybe not.

I think I'm going to ask my local garage if they can obtain parts on a fix or
return basis. Failing that I have the choice of speculation (�56+DRAT) or large
VW bills...

Keith.

    You could always wire in a 'cold-start' override switch!
    
    Flick it when cold, to start up, then when it's warm you switch it back
    again and the engine runs normally!
    
    ;-)
    
    Maybe a Pentium was used somewhere to calculate the ECU circuit
    design... AARF! (Sorry these Pentium jokes are getting a bit tiresome
    now aren't they?)

    I have an Audi 80 (2.0l 8v) and have exactly the same problem with cold
    start. I have lived with it for a while now because i know that the
    chances of a garage finding the fault without a huge bill are remote.
    The problem is worse the colder it is. For the first few seconds after
    starting it tends to die if I use the throttle at all. I will have to
    have a go at this soon as the battery and starter motor are taking a
    hammering. I was thinking of putting a meter accross the cold start
    injector to see it it gets 12v for the first few seconds. I have a
    Haynes manual but cannot find most of the components it refers to, some
    of which it shows pictures of but too closeup to see where they are.
    
    I will be very interested in the outcome and will let you know if I get
    the time/inclination to spend some time on this.  
    
    Colin 

Colin,

How old is the 80? I suspect it's quite new (2.0l), in which 
case I've checked and these engines start fine, so the problem 
almost certainly isn't one of design (as implied by the manual 
and Bosch developing a modified cold start injector). I must 
confess I haven't bought the replacement temperature sensor yet 
- the holiday and cold weather have got in the way... Still, I 
have good intentions! Have you tried simply disconnecting the 
temperature sensor to see what happens?

Tell you what, why don't we take it in turns to try to fix the 
problem (i.e. spend money). That way we'll reduce the bill by 
around 50% ;-)

Keith.

    Hi
    
    My 80 is 90 (1990 that is) - it uses the Bosch KE-Motronic injection
    system. 
    I'll buy the temerature sensor if you but the ECU.
    I have had another look at my Haynes manual and according to the
    circuit diagram (pg 324) there is very little to go wrong, there does
    not appear to be a thermo-time switch in the circuit. It looks like
    there is a temperature sensor (location unknown) and the cold start
    valve (2nd injector) and the ECU (electronic control unit - bet this is
    expensive). Depending on the coolant temperature the cold start valve
    should operate for between 1-8 seconds. They say you can replace the
    temp sensor with a 15K resistor (to simulate a very cold day I suppose)
    and disconnect the ignition coil power stage (to prevent it from
    starting accidentally), remove the cold start valve and point it into a
    jam jar. When you operate the starter you should get a nice even 'cone'
    spray of fuel for 8 seconds. You then wipe it dry and check it stays
    dry for at least a minute, to check it shuts off completely. The cold
    start valve solenoid should read 10 ohms when checked. I suppose the
    temperature sensor could be checked by measuring the resistance change
    as the engine warms up. Be careful not to disconnect anything with the
    engine running as it could cause a runaway condition. 
    I will try some of this at the weekend and let you know. The biggest
    problem is finding the temp sensor and borrowing a meter. If it's as
    cold as it has been I won't need the 15k resistor.
    Which injection system does your car have - there are 6 varieties in
    use and complexity varies.                        
    
    Colin
    
     

Some further developments...

I eventually took the advice: the car is currently in the care 
of an expert (CCC Thatcham - you reading this, Rob?) and has 
been for over a week now. As is not a complete surprise, it 
seems the problem is actually a cocktail of small problems 
manifesting themselves as poor starting and uneven 
"off-the-chill" performance.

Basically, the fifth injector isn't working correctly (ECU 
problems, �250 to replace), the cold start controller (or 
somesuch, certainly not the thermo-timer switch) isn't working 
correctly (�250) and there's some question about the fuel pump 
being up to spec (�??? where ??? is >= LOTS). Not to mention 
labour. And anyway, when the car is warmed up it works fine. So 
why am I causing myself this grief? I'm certainly not about to 
incur these costs for this "problem". Why not just live with it? 
I'm trying to talk myself into the latter...

What I am really kicking myself about is why did I let the 
dealer get away with this in the first place? When I first 
test-drove the car it had a bit of a misfire. Nothing to worry 
about, I told myself; damp, HT leads, cracked plug at the worst. 
They said they'd fix it. (Kick number 1) What they did do was 
deliver the car to my home whilst I was in Paris on business - 
but then, that's OK, they're a mian dealer, right? (Kick number 
2) OK, invoke warantee and have them fix it. After the third 
visit it was better, but not yet fixed. By now the warantee 
period had expired. So I let it lie. (Kick number 3 (&4 &5..)). 
Even though it's over 2 years now, given this problem was 
reported days after I took delivery of the car, should I have 
another go at the main dealer? I guess I don't have a rights in 
law, but maybe a moral right? Anyone had any luck in cases like 
this?

Keith.

    As far as I can see, this topic's probably the most appropriate for
    this query....
    
    I'm kindof thinking of getting hold of an Audi 80 or 90.  Insurance
    will be a nightmare for me, but I'll sort that out one way or another.
    
    I haven't really started looking yet, so can anyone give me some
    background info., such as engine/trim range, Guide 2nd hand prices
    (round about F, G, H reg).  I've more or less decided that my next
    motor will be an Audi (or Rover...hmmm...), and I'm trying to figure
    out which one I prefer, and can afford to keep!
    
    Any details greatly appreciated.

re -1

I know Keith will not like me saying this, but Top Gear a couple of weeks
back had a review of the Audi 80 as a second hand car. Quentin said they
were sound and a good buy!! The moral of Keith's saga is

1) get a long warranty
2) Keep at the dealer until it is fixed.

	Dave

Audis from 1990 onwards were designed to run on unleaded fuel and fitted with a 
catalytic converter. I don't know how well earlier models cope with unleaded.
  
Dave

Hmm, activity in this note that my note monitor missed - very 
worrying!!

Anyway, a final postscript to the cold start problems...

I found a trader of second hand Audi parts - nice chap who gave me 
more information than anyone else had. Basically, he said there are 
3 bits to go wrong: the "ECU", the cold start unit and the vacuum 
switch. I replaced the ECU and cold start unit (>�100) to no avail. 
Sigh.

I eventually tracked down "someone knowledgable" who recommened that 
I:

1: buy some VAG injector cleaner (<�5)

2: disconnect the cold start injector power lead on the starter motor. 
This means the cold start unit (which also gets involved during the 
warmup phase) would continue to function whilst preventing "choke" 
during starting. It was his assertion that the engine was flooding due 
to crap in the inlet manifold retaining petrol vapour. That combined 
with an over-healthy dose of fuel from the cold start injector was 
causing the problem. He also said that the 90 was never a first kick 
starter but was basically a very solid car.

With a huge amount of scepticism I bought the injector cleaner, ran it 
through in 2 tanks of petrol and during one of my 3000 mile oil 
changes (I know the sevrice interval is 10,000 but oil is cheap and 
when working properly keeps the metal bits apart ;-), I disconnected 
the cold start injector connection.

Guess what?

                         Problem solved!!

I was and am amazed, bewildered and somewhat ruefully, given the 
investment fixing this problem. The final solution cost less than a 
fiver. Arrgghhh!!!!

The car now starts OK (not first "swing" but very soon after) and 
everything is hunky-dory. So the advice given way bakc about seeing an 
expert was right on the money. Now what I need is advice on a painless 
way of finding an expert in the first place!!

Thanks for all the suggestions, this CLD is now closed!

Keith.

P.S. Of course, now I'm going to sell the car (the opportunity for 
something fun has turned up), but at least I won't feel guilty about 
selling it on.

Keith,

>P.S. Of course, now I'm going to sell the car (the opportunity for 
>something fun has turned up), but at least I won't feel guilty about 
>selling it on.

But are you keeping the number plate?

Too right! It's a bit of a hassle unless I do all my 
dealings through a garage, but part-ex never gives the 
true worth. Apart from that, I had one garage bloke 
practically salivating when I told him about the car (low 
miles, service history etc etc) and then offer me �2500 
:-( Perhaps they believe I can't read my Parkers guide or 
something? So, a call to DVLC to transfer the plate to our 
van and a call to Auto Trader and see what happens!

Keith.

    And the plate is?
    
    Laurie.