[urq] Hard to start - WAS - Out from winter sleep update

[Louis-Alain Richard]

Jim, just to be sure that we all speak of the same thing:

The thermo-time switch is screwed into the back of the cylinder head,
and its role is to trigger the 6th injector according to the engine temp
and for a fixed amount of time. It its failure mode is to let the 6th
injector work at each start, then it may be your problem. Part number is
043 906 163A.

The switch on the wastegate housing is called the "thermal switch for
fan run-on injector cooling" and its part number is 035 959 481B (100
Celcius). It is real easy to test: you put it in the vapor exhaust of
your kitchen boiler, and it should close when sufficiently hot. During
normal driving, after I shut the engine, mine is working intermittently
(for a few minutes) about 2 minutes after I shut the engine down. If you
want a cooler switch, try the one from a 5kt it is a 85 Celcius, 034 919
369B. 

The last bit that I think could be worth checking is the thermo-vacuum
switch 055 131 851C, screwed in the side of the head, bellow the 5th
sparkplug. This one is easy to test: at room temp, vacuum/boost is
allowed to pass through. When hot (hot tap water is enough), it is
vacuum tight. If it is failed, I guess it would allow unwanted
enrichment when the engine is hot. It could produce a hot start problem.

Last thing: try another brand of fuel. The Saab people have the same
problem with the new cars, and switching brands proved helpful in many
case. I indeed had this problem with the 9-5, long starting time, and it
happened both times after trips to see my relatives in Quebec city,
where they have their own oil refinery (Ultramar) which supplies every
other brands. Don't forgo this very simple test...

And last, last comment: I just reread my owners manual, and on page 36
Audi states that the driver must depress lightly the accelerator pedal
for ALL the starting conditions, even hot. This would allow the fuel
distributor to shoot more fuel, and get rid of any vapor locks, because
the engine vacuum would lift the plate a bit. This is not an EFI car,
even if it is fuel injected ! 

CIS rules !

Louis-Alain  


> -----Message d'origine-----
> De : urq-bounces at audifans.com [mailto:urq-bounces at audifans.com] De la
> part de Pasqualoni, James E
> Envoye : 17 avril, 2006 07:02
> A : urq at audifans.com
> Objet : Re: [urq] Out from winter sleep update
> 
> On a very similar note, if you recall my earlier post about starting
> problems (included below), it was indeed a bad ignition switch.  She
> cranks
> hard each time now.  However, I am still having hot start issues
> (insert 3B
> jokes here...).  I have replaced the thermo time switch with a new
> one, and
> the injector fan does indeed work when the lead to the thermo switch
> is
> grounded-HOWEVER, the injector cooling fan still does not seem to want
> to
> come on after an hour-long hard drive with the wife and kids
> yesterday...
> Bad new thermo time switch???  I am going to remove it and clean the
> housing
> for the switch with some contact cleaner to see if that does the
> trick.
> Guess I should order another anyways.  If the injector cooling fan
> checks
> out, what is the next logical step-fuel pump check valve, injectors,
> fuel
> distributor???
> 
> TIA,
> Jim
> 
> -----Original Message-----
> From: urq-bounces at audifans.com [mailto:urq-bounces at audifans.com] On
> Behalf
> Of Ingo Rautenberg
> Sent: Sunday, April 16, 2006 10:28 AM
> To: urq at audifans.com
> Subject: Re: [urq] Out from winter sleep update
> 
> Thanks to Mr. Bremmer and his relating of a stuck injector and echoing
> similar symptoms apparent engine flooding), I decided to replace my
> fuel
> distributor with my original.  I had replaced it with another when I
> was
> trying to diagnose what ultimately came to be an intermittent stuck
> air
> plate last year.
> 
> I'm happy to report that appears to have been the problem.
> Unfortunately, I have a serious problem with the air idle adjustment
> screw.
> I've drilled it and it still doesn't want to come out!!  Any
> suggestions?
> Alternately, does anyone have a spare good Urq TB laying around
> gathering
> dust?
> 
> TIA
> 
> Ingo
> 
> On Apr 14, 2006, at 8:28 AM, Ingo Rautenberg wrote:
> 
> > You just HAD to reply with that, didn't you?  My Urq was listening.
> > Extremely difficult warm start after 10 minutes or two hours.  Not
> > sure what yet.  Not hot out, either (though above70).  Thinking
> either
> > crank timing or position sensor or flakey Hall sending unit or
> > possible fuel Vapor lock?  Embarrassing to spend 5 minutes trying to
> > get your car to start...
> >
> > Ingo
> >
> > On Apr 13, 2006, at 11:37 AM, Pasqualoni, James E wrote:
> >
> >> Lucky man (um, not counting pearl V8's...)!  How about mine-I walk
> >> into the garage where she's parked, turn the key, and she fired
> right
> >> up.
> >> Pull her
> >> outside, shut her down and she sat outside in the sun for an hour-
> no
> >> start (no crank, no nuthing!).  Slight roll, pop clutch into
> second,
> >> starts right up.  Back her into garage.  Two hours later in the
> >> garage, fires right up again.  Back outside.  An hour later in the
> >> sun, no start.  WTF?
> >> Methinks
> >> bad ignition switch not grounding???  Damn Winter Gremlins...
> >>
> >> -----Original Message-----
> >> From: urq-bounces at audifans.com [mailto:urq-bounces at audifans.com] On
> >> Behalf Of Ingo Rautenberg
> >> Sent: Thursday, April 13, 2006 11:29 AM
> >> To: urq at audifans.com
> >> Subject: [urq] Out from winter sleep
> >>
> >> Speaking of my Urq, of course.  Parked it 3 months ago, put on the
> >> cover and unwrapped it this morning.
> >>
> >> Good news:  She started right up with no assistance from another
> >> battery or charger (try that with the V8).
> >>
> >> Bad News:  I parked it with an almost-empty tank.  $66 later she's
> >> full.
> >> Brakes need to be bled (spongy).
> >> Rear upper strut mounts need to be replaced (knew that one) Dead
> >> window regulator on Driver's side ???  Hmm.  Suggestions welcome.
> >>
> >> That's it for now.  I almost forgot how much fun she is to drive
> >> (even with the winter tires).
> >>
> >> Ingo
> >>
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> >
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> > Have an urq answer? ... Please help others by adding to the KB ...
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