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Help!

My '95 VR6 has been acting strange for some time now (she's got 27k on the
clock)... we've been to the dealer, who has (of course!) found nothing
wrong.  A run on 1551 shows no saved codes.  They had suggested that the
plugs may need to be replaced- had that done @ 21k to no real benefit.  When
that didn't fix it, they suggested that it may be the plug wires- well, $92
later for a set of the Autobahn red ones didn't fix it either.

Here's the symptoms-

1) Hesitation when cold, surging under power until fully warmed up.
2) Low-end power seems like it's being restricted somehow- there's almost
hesitation until about 3500rpm, when it lets loose, and you're GONE!
3) Surging at light throttle at most all speeds- around 25 in 2nd is pretty
bad, as is about 55 in 5th... it's real constant.
4) A rapid mild backfire when downshifting or letting off after some
throttle - while you may think you'd want your VR6 to sound like this, trust
me, you don't!
5) The idle- it's somehow *harder* (if you can imagine it) than it used to
be. Also, it will 'hang' the rpm's most of the time if you de-clutch -
example- a/c is on, dump the clutch, car will drop to ~1100rpm, then meander
slowly downwards to 900rpm.  Same thing with the a/c off, just that it hangs
around 900rpm first.

However, it starts first turn of the key, hot or cold.  Mods on the car-
K&N, deconed airbox, Autotech exhaust.

Note based on past experience- my Neon (spit!) did #3 & #5 too - that is
until the upsteam O2 sensor finally triggered a Check Engine light after
having the problem for about 10k miles!  Of course, the dealer couldn't find
the cause, but it still seemed to cost me almost $1000 (really) to fix what
turned out to be a $100 problem.  Argh!  --> please don't let my GTI go on
like this!

My dealer (Rod East VW/Audi- San Antonio Texas) has been understanding, but
is unable to even sense the problem - to quote the service advisor after
driving my car "I don't see what he's complaining about."

Help me fix it, before some Honda beats my car!

Patrick
'95 GTI-VR6 Surge-o-matic Edition

>Here's the symptoms-
>
>1) Hesitation when cold, surging under power until fully warmed up.
>2) Low-end power seems like it's being restricted somehow- there's almost
>hesitation until about 3500rpm, when it lets loose, and you're GONE!
>3) Surging at light throttle at most all speeds- around 25 in 2nd is pretty
>bad, as is about 55 in 5th... it's real constant.
>4) A rapid mild backfire when downshifting or letting off after some
>throttle - while you may think you'd want your VR6 to sound like this, trust
>me, you don't!
>5) The idle- it's somehow *harder* (if you can imagine it) than it used to
>be. Also, it will 'hang' the rpm's most of the time if you de-clutch -
>example- a/c is on, dump the clutch, car will drop to ~1100rpm, then meander
>slowly downwards to 900rpm.  Same thing with the a/c off, just that it hangs
>around 900rpm first.

Before I even got to the part where you mentioned the O2 sensor on your
Neon, I was thinking, "geez, it sounds like the O2 sensor isn't working
properly." Aside from #5, which my car does almost all the time anyway,
these symptoms are almost identical to what my '84 GTI was doing until I
replaced the sensor. I don't know what sort of info the 1551 will offer
about the O2 sensor on an OBDI car like yours, so it might be a matter of
testing it manually. I don't have my manual right in front of me, so I don't
know what the Bentley says about testing it.

Chris

>> 1) Hesitation when cold, surging under power until fully warmed up.
>> 2) Low-end power seems like it's being restricted somehow- there's almost
>> hesitation until about 3500rpm, when it lets loose, and you're GONE!
>> 3) Surging at light throttle at most all speeds- around 25 in 2nd is pretty
>> bad, as is about 55 in 5th... it's real constant.
>> 4) A rapid mild backfire when downshifting or letting off after some
>> throttle - while you may think you'd want your VR6 to sound like this, trust
>> me, you don't!
>> 5) The idle- it's somehow *harder* (if you can imagine it) than it used to
>> be. Also, it will 'hang' the rpm's most of the time if you de-clutch -
>> example- a/c is on, dump the clutch, car will drop to ~1100rpm, then meander
>> slowly downwards to 900rpm.  Same thing with the a/c off, just that it hangs
>> around 900rpm first.

One reply:
 
> Sounds like a bad connection to the engine speed sensor or throttle position
> sensor - just a guess.

Another says:

> [Oxygen Sensor]

Anyway, that's a tough one with no stored codes.  

Both the engine speed sensor and TP sensor should trigger DTCs if not
working correctly. 

Unfortunately, I don't have the real Fuel Injection and Ignitiom
Diagnostics Manual for OBD-I.      You can get this manual for $27 from
Dyment Distribution, 1-800-216-0725. 

Yes, the oxygen sensor is a possibility, but so are any number of other
things. 

For instance, it could also be a coilpack problem.  Don't buy one; swap
coilpacks with another VR6 and see if the problem follows the pack.  
OBD-II is much better at picking up ignition-related probems than
OBD-I.     

It sounds to me like that the best way to go after this, since it sounds
fairly reproducible, is to put someone in the passenger seat with a 1551
or VWTool and go through all the datablocks while the car is surging or
otherwise misbehaving.  

- -Uwe-

In a message dated 98-09-14 22:52:12 EDT, &#108;efty&#64;crl<img src=/i/dc.gif border=0 width=35 height=15> writes:

<< 
 Help me fix it, before some Honda beats my car!
 
 Patrick
 '95 GTI-VR6 Surge-o-matic Edition
  >>

Hey!
Try cleaning the trottle body(plate), with some Carb cleaner!!!
that sould smooth out the idle....(u should see all the gum that builts up)

This procedure should me a regular maintenance thing...IMHO(all cars)

But, to my knowledge, the only car maker that requires it is Volvo!(they
remove the throttle body, clean it, replace the spring, install it, and make
make the proper adjustments....$150.00 bucks)

Ohhh...also, have your Fuel filter changed!!! That helps a TON!(if its dirty)

Good luck,

DGTIVR6
6/97 Gti-vr6 DE

Funny that you guys mention this now, my car is slowly developing these
symptoms!  It all began Saturday morning on my way to see Bob Tillman and
some other listers in Boston.  I started it up, and it stalled a few times
and spewed volumes of smoke from the exhaust; now my idle is very lumpy,
varying by about 100 rpm.  I get a mild surging at low rpm's too.  The car
only seems happy revving above about 3.5K rpm.  It has been getting worse
and worse, and I sure don't have $500 for a new coil pack.  Todd just
replaced my plugs and wires about a month ago.

Later,
Greg

> Dave, to diagnose this one needs to know at what RPM and throttle position it
> occurred.  It could be anything from ignition wire breakdown, excessive spark
> plug gap, fuel starvation, or simply you hitting the rev limiter...

Umm.. my guess was about 2500-3500 rpms, I really wasn't paying much attention
until it jerked me forwards like crazy!

On the freeway, the light stutter seems to occur at cruise speeds-  maybe around
3000 rpms, give or take 300rpms.

Hope this sheds more light..

Thanks!

-Dave

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>
>> Dave, to diagnose this one needs to know at what RPM and throttle
>>position it
>> occurred.  It could be anything from ignition wire breakdown, excessive
>>spark
>> plug gap, fuel starvation, or simply you hitting the rev limiter...
>
>Umm.. my guess was about 2500-3500 rpms, I really wasn't paying much attention
>until it jerked me forwards like crazy!
>
>On the freeway, the light stutter seems to occur at cruise speeds-  maybe
>around
>3000 rpms, give or take 300rpms.
>
>Hope this sheds more light..
>
>Thanks!
>
>- -Dave


	I have had the same thing happen with my 95 GTI VR6 for the last
several months.
Car has 27000 miles new plugs. This occurs ramdomly during full power
application at RPM's from 3000 up. Under full trottle acc. when the cut out
occurs it is a complete shutdown as though the spark "stopped", then if I
slightly reduce the throttle it comes back. One time on the highway I could
repeat by just flooring the throttle and reducing maybe a 1/4 inch. The
problem doesn't happen consistantly. Did get it this morning though. Must
of antisapated the post.

	I haven't a clue as to the cause.

Paul Bauer                              &#112;bauer&#64;mit<img src=/i/de.gif border=0 width=35 height=15>
M.I.T.  Bld. 37-335                     tel     617-253-7487
77 Mass. Ave.                           fax.    617-258-5940
Cambridge, MA   02139-4309


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>
>> Dave, to diagnose this one needs to know at what RPM and throttle
>>position it
>> occurred.  It could be anything from ignition wire breakdown, excessive
>>spark
>> plug gap, fuel starvation, or simply you hitting the rev limiter...
>
>Umm.. my guess was about 2500-3500 rpms, I really wasn't paying much attention
>until it jerked me forwards like crazy!
>
>On the freeway, the light stutter seems to occur at cruise speeds-  maybe
>around
>3000 rpms, give or take 300rpms.
>
>Hope this sheds more light..
>
>Thanks!
>
>- -Dave


	I have had the same thing happen with my 95 GTI VR6 for the last
several months.
Car has 27000 miles new plugs. This occurs ramdomly during full power
application at RPM's from 3000 up. Under full trottle acc. when the cut out
occurs it is a complete shutdown as though the spark "stopped", then if I
slightly reduce the throttle it comes back. One time on the highway I could
repeat by just flooring the throttle and reducing maybe a 1/4 inch. The
problem doesn't happen consistantly. Did get it this morning though. Must
of antisapated the post.

	I haven't a clue as to the cause.


Paul Bauer                              &#112;bauer&#64;mit<img src=/i/de.gif border=0 width=35 height=15>
M.I.T.  Bld. 37-335                     tel     617-253-7487
77 Mass. Ave.                           fax.    617-258-5940
Cambridge, MA   02139-4309


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This happened to my car twice. The first time was around 25k miles and I 
kind of didn't believe anything happened -- major denial. The second 
time it happened was just before my 30k check-up. Exactly as you 
described although it was at speed, 80 or 90 mph on my way to work on 
the highway and BAM! the car just seemed to shut off. Before I even 
could bat an eye though, I was cruisin along again. 

The dealer found nothing because it was not repeatable(Of course).  They 
swapped out 3 spark plug wires that they said were going bad but nothing 
else. (I thought that was wierd, dont they always replace as a set?)  
Sorry I cant help anymore but its been over 10k miles and hasn't 
happened again. (Fingers crossed)

-Neil 95

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This may sound silly but have you checked your ignition switch? You know where
the key goes? I was driving a friends 95 when the car cut out completely and
then just shot forward again  a split second later. The symptons seem very
similar. I know he had it replaced at VW whether or not he had to pay for it I
do not know. 
LMK how that turns out curious....
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Yeah this reminds me of my 93 Corrado SLC (R.I.P.). I bought used; about 
30k on the dial; and about a week later the engine would cut out only 
mine was constantly kicking me in the a**. It seemed that every little 
movement or bump would jossle my 1.5# key chain and the switch would cut 
out.  The dealer replaced it for free (I did a lot of bitching to get my 
way). It then ran fine until I discovered that racing slicks don't work 
well in the snow!!!!! (duh) OH WELL
Moral of my story.....leave only the key you need to drive on your key 
ring to reduce stress on the ignition switch.

-B
97 cats like mine too edition
 >This may sound silly but have you checked your ignition switch? You 
know where
>the key goes? I was driving a friends 95 when the car cut out 
completely and
>then just shot forward again  a split second later. The symptons seem 
very
>similar. I know he had it replaced at VW whether or not he had to pay 
for it I
>do not know. 
>LMK how that turns out curious....
 

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I have also experienced the cut out.  Although I don't have a euro
t-body, the problem started after i installed a ported stock t-body
(never happened with the stock t-body).  Its happen three times now, and
is not repeatable.  The motor and electrical are 95 vintage.  Can anyone
else comfirm that a chip will fix the problem.

Also on the ported stock t-body, anyone notice a slightly higher idle?
Mine is about 150 rpm higher after installing it.


sm
89 golf vr6
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> If it is the "common" bad coil pack syndrome I would not expect the problem
> from being intermittent.   I have not experienced this problem, so I think
> those who have are in a better position to advise you.
>
> Does your check engine light come on when during or after the stutter?

Nope-  I wish it did.. my car's an OBD-I, so it doesn't tell you too much about
what's going on..

> If it only happens fairly seldom my guess would be a bad connection in the
> ignition or fuel delivery system.
>
> You mentioned cornering when the "stuttering" happened.  How full was your
> tank?

About 3/4 full-  I looked into that too :(

> Cornering could cause the engine to move on its mounts and stress some
> important connection...

That was my thought too-  but it could also be a pattern of using engine braking
(i.e. entering a turn) and transitioning to full throttle..

I was just outside testing this, and after rolling downhill in 3rd, downshifting to
second (no gas applied at all), and turning, then gunning it,...  stutter!!

The only other culprit may be the throttle body/TPS sensor, as Andy suggested.
Just to test it out, I unplugged it, was rewarded with a check engine light, and
then the car proceeded to run fine with no TPS!!  It idled a bit lower, but other
than that, it ran great!
I wonder if there's a procedure to test the TPS unit?  The symptoms are exactly as
Andy described-  suddenly shutting off the car at full throttle.

Earlier, if I let off a bit,  it would pick up a little, but if you floored it
again, it would die-  this was all at about 3000 rpms.  I did it several times,
then let off a little more, then gunned it, and it pulled fine.  I'm really
suspecting the TPS sensor since it ran okay after I unplugged and re-plugged it.

Do you think it may be a loose connection, or do these things go bad after awhile
like everything else?  Kinda odd, but I wouldn;t doubt anything now..
I re-swapped in the G-chip, so it's not the same as Andy's problem-  I'm thinking
bad connection/faulty TPS now.

Thanks!

-Dave

BTW: I'm cross-posting to the list to see if anyone can help w/ the TPS thing. I'm
hoping that's it-  it makes sense though-  turn down the TPS reading and it
registers as a closing throttle body.  It only does it at or near WOT too-  maybe
there's a spot where it's kinda dead, or the wires were gettign shifted enough to
affect it, as you suggested.  It would be a side cheaper than getting a coil pack,
either way!

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Dave

I think it could very well be a loose connection that get tweaked when the
engine rocks on its mounts during over-run (engine braking).  The fact that
disconnecting the throttle position sensor "fixes" it, suggests that it may be
the loose connection.

Of course, all wires have at least two ends, so a bad joint could be at the
"other end".

You must be in CA, considering you seem to be up "late"?  I am in San Jose.

Peter

[...]

>  So far I *think* all the reported occurences of this problem have
>  been with 95s?
>

Mine is. I think we are on to something here. Maybe VWoA should buy us 
all new Garrett chips!

-Neil


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> I think it could very well be a loose connection that get tweaked when the
> engine rocks on its mounts during over-run (engine braking).  The fact that
> disconnecting the throttle position sensor "fixes" it, suggests that it may be
> the loose connection.

We've been poking around in there all night, and discovered a few other interesting
things as well-  the thin vaccum lines suck!  A lot of them are very 'crispy', and
one toward the back may have had a leak in it.  I don't know if it would cause
stuttering or not, but we changed the bad looking ones already.  Tomorrow, I'll
probably go to Pep-boys and change any other ones I can get to.  One line off the
fuel pressure regulator pulled off with minimal force (gentle tug) as well. Yuck.
Something for everyone to go and check!

> Of course, all wires have at least two ends, so a bad joint could be at the
> "other end".

I'll be checking for the other end of the TPS wire tomorrow as well.  it
sdisappears under the plastic plug wire separator, so I'll probably loosen it for a
peek tomorrow.
We tested the resistance of the TPS, and all was within spec.  I'm hoping it was
just a Vaccum line thing..

> You must be in CA, considering you seem to be up "late"?  I am in San Jose.

Hehe.. yep!  We have the insomniac club thing goign on over here. I'm in Los
Angeles.  Nice that we have a 24hr. Chief auto parts (they only had 1 foot of
vaccum hose left :(   ), and a home depot as well!

-Dave

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> This may sound silly but have you checked your ignition switch? You know where
> the key goes? I was driving a friends 95 when the car cut out completely and
> then just shot forward again  a split second later. The symptons seem very
> similar. I know he had it replaced at VW whether or not he had to pay for it I
> do not know.

Hrmm.. sounds like it might be worth checking out-  Though I doubt I would get
'repeatable' results if it were the switch.  Maybe I'll try juggling the key
around when the car's on and see if it does anything.  I'll likely go out and try
that corner again tonight, to see if I can repeat the big stutter again.

Thanks for the suggestion!

--Dave

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>        I had a similar problem in my '95 GTI VR-6 when it was a year and
> a half old. No OBD 1 codes were stored. They kept the car overnight and
> told me it was a vacuum hose problem but not being more specific than
> that. I was more concerned with them finding my chip at the time which
> they never did. The problem never reoccured since.

That's funny.. a few of the thin vaccum hoses in my car are/were trashed.  We replaced most of them
with $0.19 a foot vac. hose from Pep-Boys.  The last three thin ones go out tonight.

Another thing I was wondering about was my Neuspeed P-chip.  I've been told the early ones had
different versions for ported and stock Throttle bodies.  ALL new chips are like Garrett's-  made to
work for both.  I'm going to call them with the part number, and see if it is the case. If so, I may
have to go for a reprogram from them, or see if they'll swap me for a newer chip.

I'm running the G-chip again, and yep..  pinging again, however light.  I'll have to call Mr. Lim about
that as well, but I can only send one chip at a time!!

-Dave

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