itacud

For the first time in over a year, we received a "full size" service loaner from our Audi service center. No Beattle Turbo (stick =), no A4 1.8t tip (boring), but a real adult sized 2004 A6 2.7t tiptronic, sport. In an un-offensive silver, of course. Really, it's not a bad ride, if you don't mind the looks and lack of cargo space. (Personally, I think the A6 body really needs fender flares - which pretty much makes all other forms of the A6 much prettier to look at than the standard 2.7t sedan - i.e. S6, A6 4.2, allroad.) But, asthetics are not what this post is all about.

Having a 2.7t tiptronic vehicle in my hands, I felt the need to put it to the test. Handling, of course needed examination. It's not bad. It leans less than a stock allroad, and grips decently with whatever is wrapped around the RS4 rims. Well, grip isn't tenacious, but at least it breaks predictably and can be turned in with just a hint of throttle lift. The car feels lighter than an allroad when tossed, but could still do with a bit of tuning in order to match a 402'd H-sported allroad.

Then, there's the accelleration. It's a tip, so that's the first strike against it. =) Having gotten over that, I did feel it necessary to capitalize on the one advantage a tip offers over a stick. One can repeatedly stomp on the accellerator with zero finesse, and not worry about a $2000 (dealer rates) clutch replacement! With a stick, it becomes a matter of habbit to finesse the throttle and clutch in such a manner as to acheive purposeful accelleration, w/o leaving a smoky cloud of friction material (and/or rubber). On a tip, and someone elses tip at that, there is no such worry. So, stomp the pedal I did.

Over the past couple of years, my local city street planners felt that adding numerous stop-signs to uncontrolled intersections, would punctuate the serenity of our quiet residential neighborhood. Unfortunately for them, each of these stop signs becons the start of a miniature drag-strip - perfect for testing this tip's throttle response, and for seeking out the infamous "Throttle Lag".

For a long time I've read complaints on AW of throttle lag. Some people said it was turbo lag, others said it was Drive-By-Wire Lag, and some, including myself, said it was none of the above - just a software induced throttle control intended to tame "jerk" when launching the car, and to provide controlled traction. (I cited software-architecture white papers from Bosch as evidence of my point of view.) What was certain, was that a vocal minority felt this lag to be life threatening. They claimed that upon applying the throttle, the car stood motionless for up to 2 seconds, then suddenly lunged forward with alacrity into oncomming traffic. Some indeed persued legal action with Audi. Others sold their cars or traded them in. Many just bitched about it - having experienced it or not - since that's always fun to do.

Well, I tried. I honestly tried very hard. I tried extremely hard to induce the phenomenon. Not only did I abruptly break at each stop sign, then mash the throttle to the floor as quickly as I could move my foot from one pedal to another, but I did this while staring at the tachometer, to see exactly what the engine was doing. (I watched for kids/dogs/Range-Rovers/Ferraris out of the corner of my eye.) To my surprise, the engine did very approximately what I told it to do. Repeatedly.

Sure, it's a turbo, and the tach doesn't go from idle to 6000 rpm with total linearity. TCS is on, and inherent in the ECU's programming (see white paper), so the tach diddn't leap <i>abruptly</i> from idle, spining 4 wheels with abandon. However, when I asked the tach to jump, it jumped - as quickly as it can untill power and traction are established. It never stopped moving, nor hesitated - it merely continued upwards, at the best pace it could. In return, the car acclerated smoothly and swiftly. I even induced tail slides, off-throttle, exiting corners. If on-comming traffic were coming, I'd have been long gone. I could not for one instant ellicit anything remotely resembling the awful, death-flirting, engineering bobble, known collectively as turbo/throttle/dbw- lag. It was not there!

So, my conclusion from this past day's experiment is simply that throttle-lag, as I like to call it, is just another myth. Like the Yeti, the Abominal Snowman, and the Lochness Monster, if you do see it, pleaes take a (very blurry) picture. Because I have never seen it myself.

Disclaimers: This testing was performed on a very new, 2004 A6 2.7t tiptronic sport. Maybe something has changed recently - my experiance in 2.7t tips is very limited. The last one I drove belonged to an AW member, and I was not trying to damage his drivetrain! I was merely enjoying his snacks. =) Additionally, I completely forgot that the transmission can be driven in full-auto mode. I have read from some, that using the tiptronic mode, as I did, eliminates the chance of throttle-lag. Something to check on the next loaner vehicle...

ShowMeData

The lag comes in slow, really slow, downshifting at low speeds. Keeping it in Tip mode is a different (irrelevant) experiment altogether.

Sorry, but coming from an 01 tip owner who lives with the issue daily, the above just begs for a flame. And to think I wasted all that reading time, only to find out the critical parameter in the last two sentences... every good lab report should list the assumptions and setup in the _beginning_.

happy allroader

You drove an A6. Is the software the same as the allroad? Do A6 drivers complain? I think the lag is a problem with the allroad especially because it is a bit unpredictable depending upon what very recent brake/throttle action you took before you hit the throttle. I think the issue needs continued interest/solution.

Question for those with GIAC tip chip: In "D" does it reduce lag?

Rhoomba

... live with the dreaded tip-induced lag on a daily basis.

Mind you, I am not talking about turbo lag.. not talking about gear-changing lag. This is SOLELY about starting from a standstill, or after being on the brakes at relatively slow speed, then nailing the gas. Note: I've also heard this talked about as BTL, or brake throttle lag

Mash the GO! pedal from a dead stop and count "one-one-thousand, two-one thous..." before you're rewarded with gobs of glorious thrust.

Honestly...I have seen the loch-ness monster.

And while this is marginably acceptable at a stand still (though it does irrepairable damage to your stop-light drag racer career), it can be downright nervewracking in traffic. If you are lane darting, the lag can be pronounced enough to make other drivers think "okay - you want to zip in... ZIP in... why are you waiting?")

To counter this very real threat, the educated tip driver tries to mitigate any lag by planning and timing their right foot position, to make sure the throttle position is at the right place at the right time.

I LIKE the TIP... I don't like how it makes me wait (and - sometimes, when it's urgent to get going right away, it's not just noticeable.... it's dangerous).

YMMV.

JBo_53

Also seems to be an '01 problem that has not translated to the '04's..8^)

blackfin

I will be demonstrating the throttle-lag reality on my 12/00 build date allroad at my local dealer tomorrow morning. My wife also experienced this problem the other day while borrowing my car and was pissed off because I did not tell her 'it did that!' Her car, a 2001 A6 2.8q does not ever fall on its face. Same TCU? I don't really know and I really don't care.

"It" is a software issue with the 2001 allroad's TCU; the algorithms used by this TCU are incorrect. This programming also explains the profound "CLUNK" that routinely occurs when the car is automatically downshifting at appx. 20mph, or the "BANG" that occurs while it is upshifting at appx. 35-40 mph, such as when I am attempting to gain access to the highway.

As you mentioned, there is no "S" mode for this transmission to drive in, such as in the later production models ('02/'03). I don't think I have ever read any complaints from people with those build dates.

There are updates available for this problem with the 2001 allroad, but AOA cannot get their sh*t together in determining how to introduce the updated TCUs to current owners without admitting that there is a real problem with the units! I have been writing letters to AOA for almost two years trying to get them to address this issue and change the TCU.

Last week I sent in my data to the NHTSA. Can you hear me now?

CTallroad

Call it turbo lag, call it tip lag. The tip allraod has atrocious drivetrain lag. This condition is extremely obvious when you do a "suburban" stop - you roll through a stop sign at &lt;5mph and then hit go. It loads up the engine a bit, then realizes it should really go to first instead of second, then the engine really gets to boost. Note this is most offensive when you are NOT at WOT (wide open throttle). If you simply plant your foot the car clearly is capable of downshifting and spooling up. It is the part throttle response which is purely unacceptable for an Audi IMHO.

I think if you had tried anything other than stomping on the engine you'd understand this a bit better.

Question, why the urge to bash people who drive this car and live with the problem on a daily basis? Obviously you are not as knowledgable as someone who does in fact own one - and your write up is kind of stupid when you think about it.

gragravar

long post for the return to the forum. good info, thanks, I think the newer sport software might have made the difference. Then again, I have a 6 spd, so what do I know.

itacud

But, to be complete, I went out and dragged up and down the street outside my office, also riddled with stop signs. There was no difference in the "lag" between D, S, or Tip modes - though the auto-shift algorithms seemed dopey, considering the pedal was on the floor. All exibited some small delay - around 1/10th of a second - between the throttle hitting the floor, and the tach leaving idle. There is a <i>very brief</i> slowing of the tach's movement around 1700rpm where one can feel a lethargy in the engine. Then, turbo's spool/anti-jerk control smooths power delivery, and the tach resumes it's former upwards pace, accellerating further.

Note: I'm referring to the tach with such emphasis since it's far more accurate than one's "butt" in communicating what the <i>engine</i> is doing. =) Regarding the transmission itself, at no time did the engine feel disengaged from the wheels. Engine load was apparent, and the car moved forward with out pause.

Of course, all this demonstrates is that <i>this particular car</i> is perfectly drivable.

I'm done torturing this 2.7t sport. Back to the dealer it goes! I'm looking forward to getting the (stick) allroad back. =)

itacud

I haven't been around much lately, and I wasn't sure if people were still passionate about these cars! Anger always indicates passion. =)

How're things going? Been riding much? If my Duc's battery weren't dead, I wouldn't have even driven the A6 today.