Jerky Cruise Control?

[ephone]

That is very interesting as we have never experienced that behavior. Regardless of speed and how close we are to the speed we set it is very good at maintaining that speed. The only thing I notice is the very very tiny little pulses of throttle on flat ground when it is maintaining the speed. If anything it feels like it is keeping the speed too locked down and if it let a little freedom on speed it wouldn't be as touchy feeling . Mind you this is so slight that no one riding with me says they can feel it .. really only the one driving can tell if they are paying attention.

I'm not sure if it was in this thread, but someone hooked up an ODBC monitor and caught the micro-adjustments on their computer. I wouldn't even bother to mention it to the dealer, because this something they can't fix.

 

[G-552013]

There's a setting for SCC reaction time. Mine was set to 'last minute'. Setting it to a more relaxed value made things a lot more comfortable. I think there's another for how closely it obeys the following distance, which would have a similar effect.

 

[outlaw4728]

A little late to the party. But I noticed this exact same thing on my 2020 Stinger GT. The throttle seems to accelerate and it does seem 'jerky'. I mentioned it to my dealer and they were completely dumbfounded when I tried to explain it to them and they didn't look into it. It is quite annoying though.

 

[Badal38257]

I thought it was just me, but I can feel a surge in CC too. I dont have the adaptive CC on my GT. Without reading all 15 pages in this thread, is there a solution to fix it?

 

[Lazarus.Bird]

I just took my '21 with 2000 miles on my first long trip and I am definitely noticing this. It's very subtle but noticeable for sure. I have a GT2 with adaptive CC but it happens when I'm on a flat long highway and the only car in sight. Doesn't seem to have anything to do with the adaptive CC function.

I tried staring at my tach when I felt it. It is so subtle I'm not sure I noticed a change in RPM, but also didn't want to stare at it too long while driving on CC down the highway lol.

Honestly it's pretty damn bizarre. My speed never/hardly changes. It is not a huge swing. But I can definitely feel the back and forth surge. It is annoying and kind of hard to ignore.

 

[JeffAsfbay]

I thought it was just me, but I can feel a surge in CC too. I dont have the adaptive CC on my GT. Without reading all 15 pages in this thread, is there a solution to fix it?

No, not that I have heard of (and I've been watching this thread for a long time.) One person said that their dealership acknowledged the problem, but I never saw a follow up saying what came of it. If someone with access to all the TSB's could look to see if this is in their, that would be super wonderful.

 

[rmfa]

Just reporting that my car does this too. It seems to do it more in sport mode. Kinda annoying. Glad I didn't get the dealer to look at it. I can live with it.

 

[sym]

Have any of you tried pegging it to a gear in manual mode? Especially in sport, the car only leaves 7th gear if you have cruise control on.

I have the adaptive cruise and it's smooth as butter. I've only had one or two hiccups in 50K miles.

 

[Mike_TX]

I can report the cruise in both my 2019 2.0t and 2020 3.3tt Stingers work fine, with no jerking.

 

[Stinger-Performance]

Have any of you tried pegging it to a gear in manual mode? Especially in sport, the car only leaves 7th gear if you have cruise control on.

I have the adaptive cruise and it's smooth as butter. I've only had one or two hiccups in 50K miles.

It doesn't change gears, it's just being too aggressive with the throttle so it's a little much, then let off, then a little much, then let off. I provided datalogs showing throttle, speed, etc. a few pages back.

 

[Mesmorino]

I can report the cruise in both my 2019 2.0t and 2020 3.3tt Stingers work fine, with no jerking.

The problem is that it only occurs under specific conditions, so unless you've put them under those same conditions we really don't know if those vehicles don't have the problem, or you just haven't experienced it. Like, It doesn't ever happen in my stinger anymore but that's not because it's fixed or doesn't exist; rather I simply drive around the problem. I don't set CC if I'm going at a speed where I know/it has shown that it will reproduce the effect.

Fine adjustments. Get your stinger to do those, at low-ish speeds, and then see how it behaves. Go at 60-63km/h (37-39mph), and set CC to 65km/h (40mph). Those are the specific speeds at which it happens for me, but that's not to say it wouldn't happen at faster or slower speeds. But like I said, I've just taken to getting up to speed myself and using CC to hold, rather than using CC to get up to speed.

I know exactly how to get it to do it in my car, and given the opportunity I'm certain I could get another (similar) stinger to do it. I don't think it's restricted to the 2Ls, I think it's Adaptive CCC vs non adaptive

 

[ldusseau]

Happy/sad that I found this thread. I've had my 2018 since 2020 and the cruise control has always surged at 80mph. I can't feel it on the flats but on an uphill (one in particular on a frequent drive) I can always feel it. I watch the tach and can't see a thing, speed doesn't change but I can feel the "push" in the small of my back. However my car now has about 43K miles on it and it's worse. I noticed it on the same hill last night and it's changed for the worse. Tach still wasn't moving either but it felt like it should. I read about 10 pages of this thread and it doesn't seem like anyone's had luck at the dealership or found a definitive root cause. Since the car is out of warranty I've been taking it to an independent shop. Is there anything I can point them to, other than tell them where the surge is the worst, let them feel it for themselves, and see what they can figure out? Or should I take it to the dealership where they might have some experience with this?

 

[Kazz]

This is hard to explain without a lot of words, sorry. And it's my perception after literally millions of miles of driving.

But the weak, wheezing motors have a terrible time staying around their cruise setting and so do the (in my opinion) poorly-tuned or poorly-matched turbo engines. The weak ones fall 2mph below and start to accelerate. But they're so weak they have to add a lot of pedal. Once they get where they're going they have to lift. And - due to modern fuel economy methods - when it stops accelerating the fuel delivery isn't finished and it keeps coming for a bit. Years ago when you'd lift the accelerator, acceleration would stop. Today it goes on for another second or two. It's always been very disconcerting to me. I like precision and that kind of fuel management destroys any ability to be precise. Lift and you can hear the engine keep spinning instead of starting to slow down.

Now the turbo-charged engine has that problem but with a turbo. So once the cruise control detects you're under the setting it starts to apply gas. The instant you do, the turbo starts to spool up. So now, not only does the engine still spin for a bit after you (or cruise) lift off the pedal, the turbo is coming on and that pressure now needs to be dealt with as well.

Today's engine management lets acceleration take place after you stop adding pedal. We feel that in driving without cruise (particularly in the S. Korean 2.5T and little wheezing engines of others). And we feel that when the cruise decides to quit accelerating but the engine management's not finished adding power.

SO! Blame fuel economy and related electronic tuning measures.

I recommend the Economy setting when in cruise so there is less boost going to the turbos. It still happens but is much less noticeable than on Sport, for instance.

Sorry for the novella.