A8 hitting rev limiter in auto!
06-13-2017, 11:36 AM
#1
Pro
Thread Starter
A8 hitting rev limiter in auto!
I have a 2017 C7 Z06 A8 and the last couple of days I noticed that while its in auto and in sport mode it hits the rev limiter on full throttle. Anybody else have this issue. If the car is in auto it should shift in time and not bounce into the rev limiter. I mean I'm not doing manual mode or anything, and also being in sport mode it usually has very quick shifts. It doesn't always do it but it has happened 3 times the past 2 times I drove it. It just started happening too, I have had it 6 months and it has 4k miles on it. I just don't understand why its hitting the rev limiter in full auto! The car will hit the rev limiter, lug forward, shift, and then I can hit the gas again. Any help is appreciated.
06-13-2017, 12:24 PM
#2
Le Mans Master
Odds (not a guarantee!) are you are NOT hitting the rev limiter. The A8 is cool - when it upshifts it cuts fuel ever so briefly to let the trans shift even quicker. Since that's also how the rev limit (can) work, it does sound like it, but it's not a bad thing.
In fact it's one of the coolest things about the A8, I think, once you know it's OK!
Now if you're sure about the "lug forward" stuff, then you've got a problem, I just wrote that off as memory embellishment. You should not -feel- the fuel cut I'm talking about. If you really do, you indeed have something else going on.
Ask yourself this - how many times does it hit the rev limiter on each shift? If it's once, it's likely fuel cut. If, when keeping your foot into it, it bangs off the limiter a couple or more times, then that's a rev limiter. It's also possible, I suppose, that both are happening (it's shifting AND hitting the limiter exactly once) but that's about my pay grade.
In fact it's one of the coolest things about the A8, I think, once you know it's OK!
Now if you're sure about the "lug forward" stuff, then you've got a problem, I just wrote that off as memory embellishment. You should not -feel- the fuel cut I'm talking about. If you really do, you indeed have something else going on.
Ask yourself this - how many times does it hit the rev limiter on each shift? If it's once, it's likely fuel cut. If, when keeping your foot into it, it bangs off the limiter a couple or more times, then that's a rev limiter. It's also possible, I suppose, that both are happening (it's shifting AND hitting the limiter exactly once) but that's about my pay grade.
Last edited by davepl; 06-13-2017 at 12:26 PM.
06-13-2017, 01:23 PM
#3
I'm unsure if this is related, but...
I've had the A8 fail to shift from 1st to 2nd a couple of times at the drag strip. It hits the limiter and the whole nose of the car drops and won't accelerate until I let off the gas and get back on it then it shifts normally.
I don't know for sure, but it seemed only to happen on passes when I started my burnout in manual mode in first gear, then shifted to second with the paddle. After finishing the burnout I would move the gear lever from M to D and then line up to start the pass.
I've now just decided to hold first gear when heating up the tires instead of shifting to second mid-burnout and have not had the problem since. *knocks on wood*
I've had the A8 fail to shift from 1st to 2nd a couple of times at the drag strip. It hits the limiter and the whole nose of the car drops and won't accelerate until I let off the gas and get back on it then it shifts normally.
I don't know for sure, but it seemed only to happen on passes when I started my burnout in manual mode in first gear, then shifted to second with the paddle. After finishing the burnout I would move the gear lever from M to D and then line up to start the pass.
I've now just decided to hold first gear when heating up the tires instead of shifting to second mid-burnout and have not had the problem since. *knocks on wood*
06-13-2017, 01:28 PM
#5
It is possible the rear tires have lost traction and if so the transmission isn't allowed to shift until engine power is reduced and the spinning stops. This power reduction is what you feel with the "lug forward". Do you have the PDR option? If so record one of these runs and you will likely see the TCS symbol show up.
06-13-2017, 03:05 PM
#6
Pro
Thread Starter
Odds (not a guarantee!) are you are NOT hitting the rev limiter. The A8 is cool - when it upshifts it cuts fuel ever so briefly to let the trans shift even quicker. Since that's also how the rev limit (can) work, it does sound like it, but it's not a bad thing.
In fact it's one of the coolest things about the A8, I think, once you know it's OK!
Now if you're sure about the "lug forward" stuff, then you've got a problem, I just wrote that off as memory embellishment. You should not -feel- the fuel cut I'm talking about. If you really do, you indeed have something else going on.
Ask yourself this - how many times does it hit the rev limiter on each shift? If it's once, it's likely fuel cut. If, when keeping your foot into it, it bangs off the limiter a couple or more times, then that's a rev limiter. It's also possible, I suppose, that both are happening (it's shifting AND hitting the limiter exactly once) but that's about my pay grade.
In fact it's one of the coolest things about the A8, I think, once you know it's OK!
Now if you're sure about the "lug forward" stuff, then you've got a problem, I just wrote that off as memory embellishment. You should not -feel- the fuel cut I'm talking about. If you really do, you indeed have something else going on.
Ask yourself this - how many times does it hit the rev limiter on each shift? If it's once, it's likely fuel cut. If, when keeping your foot into it, it bangs off the limiter a couple or more times, then that's a rev limiter. It's also possible, I suppose, that both are happening (it's shifting AND hitting the limiter exactly once) but that's about my pay grade.
06-13-2017, 03:07 PM
#7
Pro
Thread Starter
I'm unsure if this is related, but...
I've had the A8 fail to shift from 1st to 2nd a couple of times at the drag strip. It hits the limiter and the whole nose of the car drops and won't accelerate until I let off the gas and get back on it then it shifts normally.
I don't know for sure, but it seemed only to happen on passes when I started my burnout in manual mode in first gear, then shifted to second with the paddle. After finishing the burnout I would move the gear lever from M to D and then line up to start the pass.
I've now just decided to hold first gear when heating up the tires instead of shifting to second mid-burnout and have not had the problem since. *knocks on wood*
I've had the A8 fail to shift from 1st to 2nd a couple of times at the drag strip. It hits the limiter and the whole nose of the car drops and won't accelerate until I let off the gas and get back on it then it shifts normally.
I don't know for sure, but it seemed only to happen on passes when I started my burnout in manual mode in first gear, then shifted to second with the paddle. After finishing the burnout I would move the gear lever from M to D and then line up to start the pass.
I've now just decided to hold first gear when heating up the tires instead of shifting to second mid-burnout and have not had the problem since. *knocks on wood*
06-13-2017, 03:51 PM
#8
Melting Slicks
Interesting. Would like to hear what you find out.
06-13-2017, 08:28 PM
#9
Wow now im curious because this happens to me as well but its so random that if I took it to the dealer they would think that i'm crazy of course.. it only happens out of the blue as if the computer forgets to shift.. I have a 2016 3LZ ZO7
06-13-2017, 08:33 PM
#10
Drifting
I've experienced this a few times , it only does it after I manually change gears (paddles) ... While in Drive still, fully expecting the car to shift automatically going forward the car will fall on its face. Expecting driver input I suspect since I've changed the gears. Not sure if there's a time out feature or a reset for it to resume normal shifting ...
06-13-2017, 08:36 PM
#11
Le Mans Master
If I remember correctly (which is not a given) it will definitely bounce off the rev limiter if you're paddle shifting and then forget - which is pretty easy if the trans is still in "manual" mode because you pulled a paddle 10 seconds ago. Could it be that simple?
What I mean is you do NOT put the trans in M, but you just pull a paddle from 1-2, let's say. Now a few moments later the 2-3 upshift is due and you figure the trans will do it itself, but it won't, because you've activated "temporary Manual mode". So it hits the rev limiter at the top of 2nd gear. Then by the time you look around, it's back in Automatic mode.
If that's the case, it's almost a bug (ie: the trans should upshift at 6500 in 'temporary manual mode' even if you don't pull the paddle).
What I mean is you do NOT put the trans in M, but you just pull a paddle from 1-2, let's say. Now a few moments later the 2-3 upshift is due and you figure the trans will do it itself, but it won't, because you've activated "temporary Manual mode". So it hits the rev limiter at the top of 2nd gear. Then by the time you look around, it's back in Automatic mode.
If that's the case, it's almost a bug (ie: the trans should upshift at 6500 in 'temporary manual mode' even if you don't pull the paddle).
Last edited by davepl; 06-13-2017 at 08:37 PM.
06-13-2017, 08:46 PM
#12
Mine just does it out if nowhere in just drive mode, its not all the time just sometimes and when it happens i freak out and let go of the gas lol then i drive normally and it shifts fine.
Most of the time it shifts the way it should which is about 95% of the time but there's random 5% occasional hiccups
Most of the time it shifts the way it should which is about 95% of the time but there's random 5% occasional hiccups
06-13-2017, 11:58 PM
#13
Amat Victoria Curam
If I remember correctly (which is not a given) it will definitely bounce off the rev limiter if you're paddle shifting and then forget - which is pretty easy if the trans is still in "manual" mode because you pulled a paddle 10 seconds ago. Could it be that simple?
What I mean is you do NOT put the trans in M, but you just pull a paddle from 1-2, let's say. Now a few moments later the 2-3 upshift is due and you figure the trans will do it itself, but it won't, because you've activated "temporary Manual mode". So it hits the rev limiter at the top of 2nd gear. Then by the time you look around, it's back in Automatic mode.
If that's the case, it's almost a bug (ie: the trans should upshift at 6500 in 'temporary manual mode' even if you don't pull the paddle).
What I mean is you do NOT put the trans in M, but you just pull a paddle from 1-2, let's say. Now a few moments later the 2-3 upshift is due and you figure the trans will do it itself, but it won't, because you've activated "temporary Manual mode". So it hits the rev limiter at the top of 2nd gear. Then by the time you look around, it's back in Automatic mode.
If that's the case, it's almost a bug (ie: the trans should upshift at 6500 in 'temporary manual mode' even if you don't pull the paddle).
Last edited by HighBeta; 06-13-2017 at 11:59 PM.
06-14-2017, 12:04 AM
#14
Amat Victoria Curam
Mine just does it out if nowhere in just drive mode, its not all the time just sometimes and when it happens i freak out and let go of the gas lol then i drive normally and it shifts fine.
Most of the time it shifts the way it should which is about 95% of the time but there's random 5% occasional hiccups
Most of the time it shifts the way it should which is about 95% of the time but there's random 5% occasional hiccups
06-14-2017, 07:48 AM
#15
Race Director
Member Since: Mar 2003
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Oldtimer
Mine has never bounced off of the rev limiter in "D", but I have bounced it off of the rev limiter using the paddle shifter. I drive mine in Sport mode 99% of the time. 
06-14-2017, 08:37 AM
#16
Drifting
That's what I figured, not too big on that code. Does anyone happen to know the elapsed time for it to reset?
06-14-2017, 08:52 AM
#17
If you have used the paddle shifters while in drive, hold in the upshift paddle for more than one second and it will exit paddle mode.
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HighBeta (06-15-2017)
06-14-2017, 12:13 PM
#18
Pro
Thread Starter
No, I was on a straight stretch of road both times, I hammer the gas and it just runs into the rev limiter and lugs forward....
06-14-2017, 12:27 PM
#19
Pro
Thread Starter
Sounds like you have the same experience as me, it doesn't do it all the time but I was weird because it happened to me 3 times on 2 different days, I did drive it yesterday and didn't experience it. My concern is that the transmission in auto should know when to shift and not hit the rev limiter, I took it to the dealership and they told me to bring it in so the Corvette tech can drive it, I'm not going to take it in cause the chances he will come across this problem while he test drives it is slim. Not sure what else I can do, if it happens again I guess ill let them test drive it.
06-14-2017, 12:29 PM
#20
Pro
Thread Starter