Launch control issues

syed123

Registered User
Hi all,

To all the 272 and even s4 owners - has your car ever had issues with launching via the zf 8 speed?

The last few times I've launched from 3500rpm the car hasn't had that same sling shot rapid acceleration feel it normally gives.

It's as if It doesn't want to? Possibly straining my gearbox perhaps..

I don't know how many launches I've done but I've done quite a few in the past.

Just wondering why it's not feeling how it's supposed to.

Going to lay off the launches for now but it's annoying as I do want those sling shot launches back!

Any advice/opinions appreciated
 

Terminator x

Registered User
LC limit is 200 apparently, LC stops after that but can be reset with laptop etc.

TX.

Sent from my BBB100-2 using Tapatalk
 

syed123

Registered User
LC limit is 200 apparently, LC stops after that but can be reset with laptop etc.

TX.

Sent from my BBB100-2 using Tapatalk

Is this actually true?

I've had the car for 2 years now so 50 50 that I've done that many launches..

How exactly do I reset it using laptop?

I recall the post earlier about rs3s being limited to 200 but does that also apply to the 8 speed zf?
 

Terminator x

Registered User
Imho why would it just be the RS3 with a LC limit? Proven to exist in the RS3 section as there is a LC counter. Need vcds etc to reset it afaik. Tbf the launch in the 4 is probably harder on the car as it holds it on the brake vs a dsg car where clutch etc not engaged until launch.

TX.

Sent from my BBB100-2 using Tapatalk
 

syed123

Registered User
Imho why would it just be the RS3 with a LC limit? Proven to exist in the RS3 section as there is a LC counter. Need vcds etc to reset it afaik. Tbf the launch in the 4 is probably harder on the car as it holds it on the brake vs a dsg car where clutch etc not engaged until launch.

TX.

Sent from my BBB100-2 using Tapatalk

Fair enough, makes sense I guess.

I agree, holding the revs just using brake and also 700nm of torque going through the gearbox during a launch. Even 600 was enough but I only ever launched it once it was tuned.

Any members on here know how to reset this via vcds etc?
 

A12RNX

Registered User
I think the counter limit is BS otherwise they would have to state the limit somewhere in the manual. Also found this on the gearbox:

Eight-speed tiptronic

The eight-speed tiptronic is a classic torque-converter automatic transmission whose great strength lies in its high level of shifting and drive off comfort. Gear shifts are gentle, spontaneous, fast and highly flexible. Audi uses it in many models with a longitudinally mounted engine. Thanks to its eight speeds, jumps in rpm are small between gears, and the engine always runs near its ideal operating point. An rpm-adaptive torsion damper balances out undesired engine vibrations and enables efficient driving at extra-low engine speeds.

Also playing a large role in the efficiency ensemble is the torque converter lockup clutch with integrated damper. Under normal driving conditions, the lockup torque converter connects the transmission directly to the engine. It works with limited slip in certain situations, which – in interplay with the integrated damper – permits very low engine speeds without vibrations occurring. If the car is stationary, an internal clutch decouples the transmission from the engine, even if the “D” stage is still selected – this avoids losses due to oil circulation in the converter. As soon as the driver releases the brake, the clutch closes, and the damping effect of the torque converter ensures a smooth drive-off.

The dynamic shift program (DSP), which controls the eight-speed tiptronic, is housed in a small steel box within the gear-shift unit. It utilizes a fast processor. In the “D” mode, DSP autonomously sets the optimal shift point. To enable an efficient mode of driving, it gives preference to large gears and low engine speeds. In a second shift gate, the tiptronic allows manual intervention in the automatic transmission’s operation. This allows downshifting, e.g. on winding descents to boost engine braking or for driving in an exceptionally sporty style. In sport mode, the automatic transmission boosts driving dynamics by setting later shift points. The selector lever communicates fully electronically, without any mechanical connection with the transmission (shift-by-wire).
 

Terminator x

Registered User
@A12RNX the RS3 definitely has a LC counter, screen shots of the counter have been produced in that section.

TX.

Sent from my BBB100-2 using Tapatalk
 

A12RNX

Registered User
@terminator x i believe there is a counter I have seen people post pics of the VCDS screen grab. I can’t believe that there is a limit to something without it being told or said anywhere in the manual. Surely that is against consumer rights.
 

Terminator x

Registered User
@terminator x i believe there is a counter I have seen people post pics of the VCDS screen grab. I can’t believe that there is a limit to something without it being told or said anywhere in the manual. Surely that is against consumer rights.
There is a chap who is LC happy and his LC stopped at 200 he has screenshots.

TX.

Sent from my BBB100-2 using Tapatalk
 

Riko0073

Registered User
Other than on a track day/drag strip do people really use the launch control in daily driving?

I’d feel a bit of a knob sitting at the traffic lights with the engine revving until the lights go green personally!
 

Paul Golding

Registered User

Terminator x

Registered User
Paul the 8V isn't "old" and it absolutely is limited to 200 launches. The OP in this thread also maintains his car won't now launch after being 50/50 on maybe being that high too.

TX.

Sent from my BBB100-2 using Tapatalk
 

Daggerit

Registered User
I'd be quite surprised if our cars were limited from a gearbox stress perspective, since we don't have the same sudden clutch engagement as the s-tronic models and therefore shouldn't stress things quite as badly. Obviously it'll be a bit more than just mashing the loud pedal though. I don't know for sure, just a thought is all?
 

A12RNX

Registered User
@syed123 with the LC not working did it stop working after you have already done some that day? People have said if the gearbox gets very hot it stops LC from working that might be the case to stop people doing them back to back.

Also with the amount of torque you have going through the torque converter that will generate a lot of heat. Just a thought.

@Riko0073 i have used it a couple of times when racing a C63, m3s and other cars that are faster but the launch on these cars is incredible and gives you the edge in most cases. Plus while the car still has warranty I would rather use the feature now because if something breaks I can get it replaced, as long as I don’t abuse the function.
 

syed123

Registered User
@syed123 with the LC not working did it stop working after you have already done some that day? People have said if the gearbox gets very hot it stops LC from working that might be the case to stop people doing them back to back.

Also with the amount of torque you have going through the torque converter that will generate a lot of heat. Just a thought.

@Riko0073 i have used it a couple of times when racing a C63, m3s and other cars that are faster but the launch on these cars is incredible and gives you the edge in most cases. Plus while the car still has warranty I would rather use the feature now because if something breaks I can get it replaced, as long as I don’t abuse the function.

The last time the car did a proper launch was about 2 months ago.

I remember trying it a month back n that's when I first felt something was wrong as it didn't take it off the way it used to, it was quite average actually, even flooring it felt quicker.

It's weird because other than the launch control the car is driving very nicely.

I did also flash the tcu but I remember the launches still working fine until last month.
 

syed123

Registered User
The launches weren't consecutive either. Didn't do them instantly back to back
 

cuke2u

Registered User
There are so many variables with the gearboxes being quoted here though and this might make a heap of a difference to launch limiters. The s3 has a dsg, where as the s4 has an automatic box with a torque convertor, so one may not apply to another. Then there are the variables within the dsg boxes themselves, whether they have dry or wet clutches...
 

A12RNX

Registered User
The last time the car did a proper launch was about 2 months ago.

I remember trying it a month back n that's when I first felt something was wrong as it didn't take it off the way it used to, it was quite average actually, even flooring it felt quicker.

It's weird because other than the launch control the car is driving very nicely.

I did also flash the tcu but I remember the launches still working fine until last month.

What was the TCU flash for? Was it an Audi thing or 3rd party?
 

syed123

Registered User
What was the TCU flash for? Was it an Audi thing or 3rd party?

Tmc motorsport tcu remap - basically flashes the tcu unit to make faster gearshifts/driveability release extra torque.

I suspected this to be the reason at first and even rang the company who said they had never heard my issue before.

I don't think it is that though as apart from the launch control not working the gearchanges now and overall driveability is excellent

Plus the first few launches I did wen I first flashed the tcu were fine also
 

A12RNX

Registered User
Tmc motorsport tcu remap - basically flashes the tcu unit to make faster gearshifts/driveability release extra torque.

I suspected this to be the reason at first and even rang the company who said they had never heard my issue before.

I don't think it is that though as apart from the launch control not working the gearchanges now and overall driveability is excellent

Plus the first few launches I did wen I first flashed the tcu were fine also

Presuming you don’t have warranty left on your car? Otherwise might be worth flashing back to standard and getting Audi to have a look.
 

syed123

Registered User
Presuming you don’t have warranty left on your car? Otherwise might be worth flashing back to standard and getting Audi to have a look.

I'll probably take off the tuning box also then, my only concern is Audi will just try to put the blame on me saying that u shouldn't be launching the car that much as it causes a strain on the gearbox etc..
 

syed123

Registered User
And still have warranty
 

Dippy

Registered User
I only briefly read the above comments so sorry if I missed something.

LC only applies to s-tronic because the clutch release needs to be controlled by the TCU. Clearly it causes clutchpack wear which is why Audi included the counter.

On the other hand tip-tronic has a torque converter gearbox such as the ZF. This is designed to allow the engine to rev whilst the gears are engaged and the brake applied (which is what happens at every stop junction and traffic light). So LC is not needed (or you could say that it is "inherent"). Due to the action of the stator there can be torque multiplication and this is highest near the stall point. However since the transmission fluid is viscous, a lot of heat can be generated by maintaining this for a period of time, so it is best to only rev the engine to near the stall point right before you want to launch.

I'm not sure why the OP's recent launches did not feel so good but I'd suggest that heat may have been an issue. With the recent hot weather the engine and gearbox will be hotter than normal and perhaps the launches are raising the temperature to such a level that the ECU is intervening and reducing engine torque.
 

syed123

Registered User
I only briefly read the above comments so sorry if I missed something.

LC only applies to s-tronic because the clutch release needs to be controlled by the TCU. Clearly it causes clutchpack wear which is why Audi included the counter.

On the other hand tip-tronic has a torque converter gearbox such as the ZF. This is designed to allow the engine to rev whilst the gears are engaged and the brake applied (which is what happens at every stop junction and traffic light). So LC is not needed (or you could say that it is "inherent"). Due to the action of the stator there can be torque multiplication and this is highest near the stall point. However since the transmission fluid is viscous, a lot of heat can be generated by maintaining this for a period of time, so it is best to only rev the engine to near the stall point right before you want to launch.

I'm not sure why the OP's recent launches did not feel so good but I'd suggest that heat may have been an issue. With the recent hot weather the engine and gearbox will be hotter than normal and perhaps the launches are raising the temperature to such a level that the ECU is intervening and reducing engine torque.

Agree with a lot you've said - the launches simply don't give that elastic band feeling slingshot feel I normally would get, so I'm assuming it must be the recent heat aswell

I'm going to probably give it a rest with the launches for now I think.

But I hope I get those launches back soon!
 

SRB93

S5 B9 Coupe - Glacier White
I'd suggest letting someone else doing it whilst you're in the passenger seat (Permitting you'll allow anyone to do it) and you may feel the difference.
 

syed123

Registered User
I'd suggest letting someone else doing it whilst you're in the passenger seat (Permitting you'll allow anyone to do it) and you may feel the difference.

That wouldn't work lol,

Believe me there's a night and day difference.

Normal flat out acceleration feels stronger when it's meant to be the other way round.
 

Flowrider99

Registered User
I've never seen the need to use launch control as my S5 pulls away fast enough for me as it is. Does LC make that much difference?
 

syed123

Registered User
I've never seen the need to use launch control as my S5 pulls away fast enough for me as it is. Does LC make that much difference?

For my car it does.. When my car was stock it did 0 60 5 seconds dead with launch and 5.2 without

With the way it is now it does 0 60 in 4.3 with LC and around 4.8/4.9 flat out
 

Terminator x

Registered User
LC snaps your head back, very different imho.

TX.

Sent from my BBB100-2 using Tapatalk
 

Paul Golding

Registered User
LC snaps your head back, very different imho.

TX.

Sent from my BBB100-2 using Tapatalk
Much less so in a non-quattro, as I found out at the weekend. Turning off TC makes it all a bit on the noisy side:tearsofjoy:. But at least I gave it a go.
 

bennymac

Registered User
interesting thread I have only used LC to show off and wow …. nearly everyone feels sick after it and I really struggle to hold on ha ha.
absolutely huge difference on mine to a flat out pull from stationary
 

syed123

Registered User
interesting thread I have only used LC to show off and wow …. nearly everyone feels sick after it and I really struggle to hold on ha ha.
absolutely huge difference on mine to a flat out pull from stationary

S4 or 272?

I miss mine! Still not back to the way it should be.

Will get a vcds check done very soon I think as not much left I can do..
 
Top