The definitive word on the "throttle lag" issue (hopefully)
#11
FWIW, I believe this delay is coded INTO the ECU/TCU. The definitive way to find out would be to purchase the GIAC or APR tunes and compare the difference to OEM. They both claim to have significantly improved throttle responsiveness...
#12
It would be interesting to analyze the tunes, or if APR or GIAC has any word on it, because no one with the tune complains of lag. People previously with the lag say it is disappeared or much improved after the tune.
#13
My issue is #2. It occurs in a straight line or in a turn. If you brake to slow down but don't come to a complete stop, and immediately try to accelerate again (either lightly, moderately, or aggressively), there is a significant lag, or pause, where there is virtually no reaction. It's as if the ECU is saying "you just applied the brake, are you sure you meant to accelerate again so soon?". After a couple seconds the motor responds as you would expect.
Once you get used to this, you learn to not try to scoot across traffic after slowing down, or pulling into traffic immediately after braking. I consider this a safety issue, but I also believe this was intentionally programmed in.
I should add, it is less in sport vs auto / comfort. So either the programming changes when you change modes, or there is some connection to quicker gear selection. My experience makes me believe the former.
Last edited by CiscoS4; 01-17-2014 at 12:35 PM.
#14
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#2 is also my experience. I bought a new brake light sensor for $15 on eBay: going to try that as one poster in the other thread said that was the problem with his Q7. Not sure it's the correct part though; I emailed and PM'd him but never got a confirmation.
Unfortunately, I am in Taiwan for two weeks on business and won't get to try this for awhile. Could be worse: my colleague here paid more for his Q5 than I did for my S6!
Unfortunately, I am in Taiwan for two weeks on business and won't get to try this for awhile. Could be worse: my colleague here paid more for his Q5 than I did for my S6!
#15
This is keeping me away from an S6
I didn't exhaustively read the other long thread, but it seems there are two issues that people are calling "throttle lag":
1. Lag off the line from a standing start, in the traditional sense of lag when talking about turbo motors.
2. Lag when getting on the throttle immediately after braking.
Your experiments are more relevant to case #1. I personally do not experience this at all and have great throttle response off the line either in drive or sport modes.
My issue is #2. It occurs in a straight line or in a turn. If you brake to slow down but don't come to a complete stop, and immediately try to accelerate again (either lightly, moderately, or aggressively), there is a significant lag, or pause, where there is virtually no reaction. It's as if the ECU is saying "you just applied the brake, are you sure you meant to accelerate again so soon?". After a couple seconds the motor responds as you would expect.
Once you get used to this, you learn to not try to scoot across traffic after slowing down, or pulling into traffic immediately after braking. I consider this a safety issue, but I also believe this was intentionally programmed in.
1. Lag off the line from a standing start, in the traditional sense of lag when talking about turbo motors.
2. Lag when getting on the throttle immediately after braking.
Your experiments are more relevant to case #1. I personally do not experience this at all and have great throttle response off the line either in drive or sport modes.
My issue is #2. It occurs in a straight line or in a turn. If you brake to slow down but don't come to a complete stop, and immediately try to accelerate again (either lightly, moderately, or aggressively), there is a significant lag, or pause, where there is virtually no reaction. It's as if the ECU is saying "you just applied the brake, are you sure you meant to accelerate again so soon?". After a couple seconds the motor responds as you would expect.
Once you get used to this, you learn to not try to scoot across traffic after slowing down, or pulling into traffic immediately after braking. I consider this a safety issue, but I also believe this was intentionally programmed in.
#16
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Can i just chime in here on this OLD thread? As an Audi owner of 4 audis in the past. 2007 A6 4.2, 2009 A3 2.0T, 2009 A4 2.0T, 2010 S5 4.2 The ONLY one that does not have this 'lag' issue is my S5 and that's because it's a manual transmission. Recently, I had a 2013 A6 loaner and I was reminded of this lag while accelerating and decelerating. IMO, it's a transmission issue(flaw, feature, whatever). Total lag off the line. My A3 was the worst at it. I would accel and the car would immediately try to shift to second after a terrible boggy launch. My workaround was rolling starts. This tranny seems to like that kind of start. Let it roll and then GO. Or switch to M and use your flappy paddles. My S5 is a true pleasure because, let's face it, manual transmissions reduce the complexity between driver and engine.
#18
Here's the definitive answer
There are a couple of "lagging" items. One pertains to the engagement disengagement of the DSG clutch packs when you're at certain RPMs. This happens because within a certain window, the car will begin to upshift of downshift to a different gear if you're off throttle. This will cause disengagement, and if you press the pedal in that gear again, there will be a delay for it to re-engage the clutch packs. Some of this is remedied with how we re-calibrate the torque requests in the S-Tronic transmission software, however it's impossible to remove all of this type of behavior. The second "item of delay" relates to the drive-by-wire throttle mapping on direct injection vehicles. OEMs use certain calibration tricks to tip toe around federal regulations for emissions. We fix these items to make the vehicle immediately responsive.
#19
Work around?
I believe that this is the correct explanation for the "lag". I see it when I am getting off the highway and brake at the bottom of the ramp before entering traffic. I slow from about 60 to perhaps 10 mph and I am sure the tranny downshifts given enough time. If I stop, there is no problem, but if I roll without stopping I probably hit the throttle before downshift. I will try manual downshifts under these circumstances - before I accelerate - to see if it makes a difference.
What is the main advantage to a DSG tranny anyhow? Audi seems to prefer the non DSG in other applcations.
What is the main advantage to a DSG tranny anyhow? Audi seems to prefer the non DSG in other applcations.
#20