Jerky automatic transmission shifting

[I Stung U]

is getting the tranny reset an automatic free thing under warranty in U.S.A. or other Canadian dealers ?
local one told me it is free, but I still have to agree to pay (on paper) for the service check, and if the mechanic finds the problem to be there and it being a reset issue, then there's no charge, but if finds nothing wrong or whatever, I may have to pay the service call.
I told them No, I don't want to agree to that. I feel it and it's there, just book me in for a reset... but they kept saying I have to get it tested and approved for that.
I do suspect the mechanic will feel the jerky and aggressive down shifts from 4-3-2, and should be o.k., but don't like to trust these stealerships with anything... Especially after telling me I need two of my lower arms replaced when I hit a curb, but 3 other shops found nothing wrong with them (those who followed my strut problem).

Any feedback, especially from Canadians, if I can just push for a reset, period ?
And will the reset fix the mis-shift from 3 t0 4 ? I sometimes have to tapp 2-3 times to get the upshift from 3-4 go

 

[Buklau]

is getting the tranny reset an automatic free thing under warranty in U.S.A. or other Canadian dealers ?
local one told me it is free, but I still have to agree to pay (on paper) for the service check, and if the mechanic finds the problem to be there and it being a reset issue, then there's no charge, but if finds nothing wrong or whatever, I may have to pay the service call.
I told them No, I don't want to agree to that. I feel it and it's there, just book me in for a reset... but they kept saying I have to get it tested and approved for that.
I do suspect the mechanic will feel the jerky and aggressive down shifts from 4-3-2, and should be o.k., but don't like to trust these stealerships with anything... Especially after telling me I need two of my lower arms replaced when I hit a curb, but 3 other shops found nothing wrong with them (those who followed my strut problem).

Any feedback, especially from Canadians, if I can just push for a reset, period ?
And will the reset fix the mis-shift from 3 t0 4 ? I sometimes have to tapp 2-3 times to get the upshift from 3-4 go

I had the same experience from visiting the Kia dealership before. Said I would have to pay them like $100 to check and if it’s present it will be free of charge but if not I get charged? Wtf?

Hey, this is random but I spotted you back in October on Avenue before. Lol

 

[siegs7]

Thanks to all who responded. Let me try and answer all the questions:

I haven't experimented at all with the paddle shifters, no. I have experimented a lot changing the Drive Modes and have learned that it doesn't make any difference which Drive Mode I'm in, the jerkiness is present - It is less noticeable in Sport Mode, but I assume that is because the the gears rev longer at a higher RPM as you accelerate, or as you break.

I have had the learned codes cleared 3 times since November 2020, so it doesn't seem to last long. Clearing the codes is covered under warranty - At least here in the US it has been for me.

I have called Kia Premium Care and they opened a case, but they said there is nothing they can do on their end. They recommend that I take my Stinger to a different Kia Service department and have them assess my concern. They also said that they're pretty sure this is normal behavior as the Stinger is designed to learn driving patterns as a safety feature and their team cannot do anything unless a Kia Service Department calls them to escalate. Grrrr!

One thing that is most likely the culprit is, I live in a community where there are speed humps immediately as I leave my driveway, so I accelerate, then slow down about 4 times as I leave my neighborhood. I made the mistake by telling the Kia Service this detail and now they're telling me that basically it is my fault for the reason why the transmission continues to learn this driving pattern and the jerkiness. My argument with that is, I drove the Stinger for 2 years free of this issue, driving over the same speed humps. All of a sudden, in November 2020, this became an issue. I cannot imagine that the transmission didn't only begin learning and saving driving codes after 2 years?!

I had the K900 for 4 years prior to the Stinger and never had this issue. I'm pretty sure that the transmission is also the same 8-speed transmission?

 

[MerlintheMad]

Thanks to all who responded. Let me try and answer all the questions:

I haven't experimented at all with the paddle shifters, no. I have experimented a lot changing the Drive Modes and have learned that it doesn't make any difference which Drive Mode I'm in, the jerkiness is present - It is less noticeable in Sport Mode, but I assume that is because the the gears rev longer at a higher RPM as you accelerate, or as you break.

I have had the learned codes cleared 3 times since November 2020, so it doesn't seem to last long. Clearing the codes is covered under warranty - At least here in the US it has been for me.

I have called Kia Premium Care and they opened a case, but they said there is nothing they can do on their end. They recommend that I take my Stinger to a different Kia Service department and have them assess my concern. They also said that they're pretty sure this is normal behavior as the Stinger is designed to learn driving patterns as a safety feature and their team cannot do anything unless a Kia Service Department calls them to escalate. Grrrr!

One thing that is most likely the culprit is, I live in a community where there are speed humps immediately as I leave my driveway, so I accelerate, then slow down about 4 times as I leave my neighborhood. I made the mistake by telling the Kia Service this detail and now they're telling me that basically it is my fault for the reason why the transmission continues to learn this driving pattern and the jerkiness. My argument with that is, I drove the Stinger for 2 years free of this issue, driving over the same speed humps. All of a sudden, in November 2020, this became an issue. I cannot imagine that the transmission didn't only begin learning and saving driving codes after 2 years?!

I had the K900 for 4 years prior to the Stinger and never had this issue. I'm pretty sure that the transmission is also the same 8-speed transmission?

I guess the next thing to do is reflash (aaagain), and try driving with paddles and see if that clears anything up. Paddles in Smart mode, an interesting proposition.

 

[I Stung U]

I had the same experience from visiting the Kia dealership before. Said I would have to pay them like $100 to check and if it’s present it will be free of charge but if not I get charged? Wtf?

Hey, this is random but I spotted you back in October on Avenue before. Lol

I'm sure they'll notice the strong downshifts. I'll just agree to it to get it in the shop, and for some crazy reason the guy says they don't feel anything, I'll just ask for the General manage of the dealership and take him out for a drive.. and freak out on them if need be... but I assume they'll just do the reset.

Ya, that's me.. I have a clients rental unit for rent there. Likely there to show it to a prospective tenant.
Nice catch !

 

[ryan1stinger]

The aggressive down-shifting is part of the design of a "sporty" car. Try ECO mode if you want something closer to a traditional American car automatic. Also, as is the case with a manual transmission car that the engineers were trying to mimic, you don't ride the brakes. You take your foot off the gas and let the car/engine slow you until steady application of the brakes is needed to bring the car to a halt. By the time you have let the engine braking do its job, the remainder braking phase should be firm and smooth. If your foot is usually on the gas right up until the moment you need to push the brake pedal to deal with traffic, you aren't driving in a way that the car thinks equals smooth and steady. It reads "spirited" or "aggressive" from those inputs.

The only time I have ever had the car behave as you describe, is if beforehand I have either stabbed the brakes because I wasn't paying attention to traffic closely enough and needed heavy braking, and/or combined that with stabby application of the throttle, either of which signals to the transmission to go into a slightly more aggressive mode (even in Comfort). Before getting any TSB applied, I would try to pay attention to driving and see if the car is behaving as if it had a manual transmission, or if there is something wrong.

The car never speeds up while coasting, but some people get confused because the engine will speed-up and slow-down as it down-shifts to ensure the car is in the right gear if you choose to apply throttle (something older automatics did not do well at all). The surges of braking g-force as each lower gear is engaged might fool people into thinking the car is not continuously decelerating, but it is, just at inconsistent rates--and it's the same experience in a manual transmission car or in a racing car. The goal, as it is in a race car or a manual shifter, is to use the brake pedal the least possible, but when you do use it, it's to more seriously slow the car for an upcoming corner or to come to a stop.

The Stinger (programming) does not perform well with the typical North American "race between stop lights," jerky, stop-and-start driving style. If you try forcing only smooth application of the throttle and brake, just as a test, it might be revealing. And smooth does not mean little. You can drive as aggressively and fast as you want (the car actually works better when you ask it to really go), but ensure the pedal application is smooth and deliberate, not stabby or jerky.

If you want 80% throttle, you have two choices: jab the throttle to 80% or smoothly push it to 80% taking about one second to get there (the time it takes to say "one-one thousand"). When I do the first one, the car sometimes hesitates and feels like it has major turbo lag or some other problem. What is actually happening is the jab is setting the car into emergency alert mode--it pauses to figure out how many gears to drop, curtails the engine rpm so when it figures out what gear to use it there is a proper clutch action to not damage anything, etc. Feels to us like a uncomfortable delay. If I drive the car properly (like a manual), using the accelerator position to go faster or lifting to slow the needed amount (like a mild version of an electric car) and goose the throttle using the smooth but firm method, the car responds instantaneously (even in Comfort mode).

Moving to Sport mode mostly just puts the car into the higher alert state--assuming you already know you want to be more aggressive. It's not providing any different performance. The rate of application and de-application of the pedal forces is a major input into the car's electronic wizardry (that we cannot change), so learning to work with it may be better than getting a reprogramming (that we know from experience with many other cars in the past decade can create as many new issues as it resolves). Remember, just taking your foot off the gas pedal suddenly as opposed to smoothly counts as a mild alert to the car.

Let us know if this easy-to-implement test reveals anything.

I have a 2018 GT2, drive by wire, RWD and intermittently I experience the same issue where I jab the throttle to the floor and I feel as if the car is in limp mode. I completely lift off the throttle and punch it again and away I go. I have a tuned ECU and I thought what I was experiencing was over boosting, and maybe it is or may it's a TCU issue. Have you raised this issue with KIA?

The other intermittent issue I experience when in D, driving at let's say 45, 60 or 75 and quickly fully depress the throttle the car downshifts, but not to the idle gear for the maximum power band of 5k RPMs, rather it downshifts to a gear where the RPMs are at 3.5K and the car feels sluggish compared to 5k. Have you experienced this?

 

[SpaceGhost]

This car should have a manual and an automated manual option. Can get that in GTI. I have two stingers one with the rough shift but even the other one the transmission still sucks.

 

[RVance]

This car should have a manual and an automated manual option. Can get that in GTI. I have two stingers one with the rough shift but even the other one the transmission still sucks.

I get the occasional clunky shift at low speed/rpm into second or third. But when I hammer it in Sport Mode through the infamous Smith River canyon on H199, the trans is very intuitive and operates flawlessly. Paddles could be a little quicker, but I'm usually too busy to notice.

 

[Marc Collins]

I have a 2018 GT2, drive by wire, RWD and intermittently I experience the same issue where I jab the throttle to the floor and I feel as if the car is in limp mode. I completely lift off the throttle and punch it again and away I go. I have a tuned ECU and I thought what I was experiencing was over boosting, and maybe it is or may it's a TCU issue. Have you raised this issue with KIA?

The other intermittent issue I experience when in D, driving at let's say 45, 60 or 75 and quickly fully depress the throttle the car downshifts, but not to the idle gear for the maximum power band of 5k RPMs, rather it downshifts to a gear where the RPMs are at 3.5K and the car feels sluggish compared to 5k. Have you experienced this?

First of all, just as a general note, jabbing the throttle is always a bad idea as anyone who drives a true manual transmission will attest. Apply the throttle smoothly, but quickly.

If you jab the throttle, two things happen simultaneously on the RWD car--traction control goes into panic mode to prevent rear wheel spin, and, the transmission goes into panic mode and tries to figure-out how many gears to down shift...not so easy when there are eight in total versus the olden days with many fewer. In the AWD car, we typically only have the transmission annoyance to deal with unless it's on ice or snow.

Maximum torque in the twin-turbo V6 comes in at a very low rpm. Maximum torque is what is required for acceleration, not high rpm/maximum power (that's needed to reach and sustain top speeds...that are so high in the Stinger none of us will be able to reach them on public roads). I think if you measure actual acceleration forces, you'll discover that the lower rpm is sufficient even though there is a lot less drama and noise involved. You can experiment with the car in manual shift mode to confirm this. One reason I love driving the Stinger is you can easily keep-up with any traffic in the city and reach legal speeds on most super highways without surpassing 2,000 rpm!

A tuned ECU will interfere with this process, as it will likely be sending additional torque that will trigger unintended additional TC intervention. The TC is tuned for the normal car. Again, experiment with manual shifting and TC turned off to see what happens. The nannies are designed to prevent stupidity from triggering a loss of control, but they also inevitably curb the performance near the edge of control where if the driver was paying full attention there should not be a problem. Using the better safe-than-sorry settings is approved by all the corporate lawyers. Same reason we have to push a button to get into Park...because we can't collectively be trusted to be sure the car is actually in P before hopping out of the car and getting run over by it.

 

[ryan1stinger]

First of all, just as a general note, jabbing the throttle is always a bad idea as anyone who drives a true manual transmission will attest. Apply the throttle smoothly, but quickly.

If you jab the throttle, two things happen simultaneously on the RWD car--traction control goes into panic mode to prevent rear wheel spin, and, the transmission goes into panic mode and tries to figure-out how many gears to down shift...not so easy when there are eight in total versus the olden days with many fewer. In the AWD car, we typically only have the transmission annoyance to deal with unless it's on ice or snow.

Maximum torque in the twin-turbo V6 comes in at a very low rpm. Maximum torque is what is required for acceleration, not high rpm/maximum power (that's needed to reach and sustain top speeds...that are so high in the Stinger none of us will be able to reach them on public roads). I think if you measure actual acceleration forces, you'll discover that the lower rpm is sufficient even though there is a lot less drama and noise involved. You can experiment with the car in manual shift mode to confirm this. One reason I love driving the Stinger is you can easily keep-up with any traffic in the city and reach legal speeds on most super highways without surpassing 2,000 rpm!

A tuned ECU will interfere with this process, as it will likely be sending additional torque that will trigger unintended additional TC intervention. The TC is tuned for the normal car. Again, experiment with manual shifting and TC turned off to see what happens. The nannies are designed to prevent stupidity from triggering a loss of control, but they also inevitably curb the performance near the edge of control where if the driver was paying full attention there should not be a problem. Using the better safe-than-sorry settings is approved by all the corporate lawyers. Same reason we have to push a button to get into Park...because we can't collectively be trusted to be sure the car is actually in P before hopping out of the car and getting run over by it.

thanks for the feedback.

I’m probably not jabbing it as much as I think I am, but in order for the downshifts to occur quickly you do have to quickly depress the throttle.

As for peak acceleration that can actually occur at peak horsepower depending upon gearing and such.



here is a great video on that. My car is accelerating faster at high HP and lower torque rather than higher torque and lower HP. It’s very apparent to my butt dyno, nothing to do with the sound from my car.

My tuner shared that methanol will cause a hesitation event when getting off the throttle and back on. AFRs will show a rich condition when this occurs. I’m using WMI and I think that may be occurring as the only time I can recall this lack of power is after I’ve already been on full throttle. In my case this is the more likely the scenario than TC, however I have certainly felt and I’m familiar with TC kicking in, so it could be a combination.

 

[Marc Collins]

thanks for the feedback.

I’m probably not jabbing it as much as I think I am, but in order for the downshifts to occur quickly you do have to quickly depress the throttle.

As for peak acceleration that can actually occur at peak horsepower depending upon gearing and such.



here is a great video on that. My car is accelerating faster at high HP and lower torque rather than higher torque and lower HP. It’s very apparent to my butt dyno, nothing to do with the sound from my car.

My tuner shared that methanol will cause a hesitation event when getting off the throttle and back on. AFRs will show a rich condition when this occurs. I’m using WMI and I think that may be occurring as the only time I can recall this lack of power is after I’ve already been on full throttle. In my case this is the more likely the scenario than TC, however I have certainly felt and I’m familiar with TC kicking in, so it could be a combination.

There are two aspects to TC, which is actually a more complex system (hence why they keep inventing new acronyms). One part is activating the ABS on individual wheels to prevent slippage and the other is retardation of the engine. These two have to work in concert with the transmission, so I think you are on the right track that if even another retardation cause/event is occurring due to the methanol or any other ECU-related trigger, it's going to cascade into confusing the whole system.

 

[ryan1stinger]

There are two aspects to TC, which is actually a more complex system (hence why they keep inventing new acronyms). One part is activating the ABS on individual wheels to prevent slippage and the other is retardation of the engine. These two have to work in concert with the transmission, so I think you are on the right track that if even another retardation cause/event is occurring due to the methanol or any other ECU-related trigger, it's going to cascade into confusing the whole system.

Thanks for the info. I’ve disabled TC for future testing.

 

[St1nger Guy]

So I've noticed when coasting when press the gas pedal again there is always a small jolt. I started wondering if maybe my gas pedal has something wrong with it and not the transmission because it always does it hot or cold. To test this theory I set the cruise and then used the cancel button to make the car coast, then hit the resume so the car would get back up to speed by applying the throttle. Sure enough, the cruise doesn't have this jolt when going from coasting back into throttle. Is there a way to calibrate the throttle pedal? It acts like it just skips over the first little bit if movement and then opens the throttle plate abruptly at like 3 to 5% causing the jolt. Wish there was another stinger owner around here that would let me test their pedal. At least I know my trans isn't the issue.

 

[Marty4life]

Hey guys - I didn’t go through all 9 pages here but I have a 2019 GT1, had it for 6 months, just hit 2000 miles. Recently it’s developed a VERY pronounced/jerky DOWNshift from 2nd to first as you’re coasting/light brake to a stop. Much worse when cold but never fully goes away. TSB/reflash? Is there a procedure to reset the shift points or is that dealer only? Thanks

New to this forum. Have the same issue with my 2020 GT1. Wondered if you ever got any feedback on your question.

 

[St1nger Guy]

I haven't tested the possible solution yet to know if it works but if it does I'll post it in here.

 

[Marty4life]

I haven't tested the possible solution yet to know if it works but if it does I'll post it in here.

Thanks.

 

[G70 Owner]

Or just read back a couple pages…

 

[St1nger Guy]

Or just read back a couple pages…

I've read this entire thread, I didn't see a specific post about the pedal issue and how to solve in this thread. The repair manual states to reset the TPS you need to press the start button twice but not press the brake pedal so it won't start the engine and let it sit like that for 1 minute. Then press the start button with the brake to start the engine and let the car idle for 15 minutes then shut it off, then do step one again for 1 minute then press the start button again to shut everything off. Next start it should be reset. I am going to attempt doing this tonight and see how it goes.

Something else that was mentioned in the manual is it could be a dirty throttle body causing issues, in which case it needs to be cleaned. That will be the next thing I try if option 1 doesn't fix it.

 

[G70 Owner]

I've read this entire thread, I didn't see a specific post about the pedal issue and how to solve in this thread. The repair manual states to reset the TPS you need to press the start button twice but not press the brake pedal so it won't start the engine and let it sit like that for 1 minute. Then press the start button with the brake to start the engine and let the car idle for 15 minutes then shut it off, then do step one again for 1 minute then press the start button again to shut everything off. Next start it should be reset. I am going to attempt doing this tonight and see how it goes.

Something else that was mentioned in the manual is it could be a dirty throttle body causing issues, in which case it needs to be cleaned. That will be the next thing I try if option 1 doesn't fix it.

Im not sure what youre talking about with a pedal issue; I was replying to this Marty guy who was asking a guest account about his downshifting issue

 

[St1nger Guy]

Im not sure what youre talking about with a pedal issue; I was replying to this Marty guy who was asking a guest account about his downshifting issue

Ah, well that splains it.