Jerky automatic transmission shifting

[rocket23]

There is TSB (my service record says it's a recall) It is called a ''static gear shift logic''. Probably the remedy that is ailing most of the symptoms in this thread.......btw, less fluid means soft or no shifting at all......for the record.

 

[Revvdmedia]

I been having shifting issues around 2nd and 3rd gears, as well as loss of power after resuming movement after stopping at a stop sign. As well as a few instances of loss of power and having the traction control light come while moving on all under normal driving. Took it to dealer for the concern and was told that my K&N intake could be the issues as the fuel injectors can not keep up... And this is what I was told "KIA" said to them.

It must be the fuel injectors not keeping up. You know, because the guys tuning the cars and running over 430whp are all leaning out and detonating...

 

[capnsharpe]

At the risk of upsetting certain Fanboys again... I asked the dealer to take a look at the transmission fluid as I also experienced the occasional hard shift in comfort and sport modes. They found a small amount water in the transmission fluid. The cause is a cracked seal similar to an o ring. They ordered the part and expect it no later than Tuesday but it will take 2 days replace. They said they'd have a loaner ready. I've never been so happy to have a 10 year warranty.

 

[RVance]

At the risk of upsetting certain Fanboys again... I asked the dealer to take a look at the transmission fluid as I also experienced the occasional hard shift in comfort and sport modes. They found a small amount water in the transmission fluid. The cause is a cracked seal similar to an o ring. They ordered the part and expect it no later than Tuesday but it will take 2 days replace. They said they'd have a loaner ready. I've never been so happy to have a 10 year warranty.

Oh boy. Going on a long trip. No time to see dealer before I leave. But good to know I'm not hallucinating. About the transmission.

 

[Jwolf]

At the risk of upsetting certain Fanboys again... I asked the dealer to take a look at the transmission fluid as I also experienced the occasional hard shift in comfort and sport modes. They found a small amount water in the transmission fluid. The cause is a cracked seal similar to an o ring. They ordered the part and expect it no later than Tuesday but it will take 2 days replace. They said they'd have a loaner ready. I've never been so happy to have a 10 year warranty.

While that is concerning, and I will have my dealer look into it at my next service, please keep us informed if that changes anything in the behavior of the shifting. It may just be a coincidence, but we all want to know.

 

[RVance]

I'm going from Crescent City to Vista, CA on I-5. About 750 miles each way. Grapevine and LA/ Orange County will tell the tale.

 

[Marc Collins]

There is TSB (my service record says it's a recall) It is called a ''static gear shift logic''. Probably the remedy that is ailing most of the symptoms in this thread.......btw, less fluid means soft or no shifting at all......for the record.

There is a known update to the shift logic that seems like it is finally here. The initial purpose was to add a proper manual mode to the transmission while in Sport--i.e., it won't revert to "D" when you come to a stop and it won't automatically up-shift when you approach the rev limiter. The programming the car came with is similar to what you would get in a minivan or econo-car. So, the question is while applying the manual mode that should have been in the car from the outset, did they change anything else? Any changes could vary by drive mode. And they could have adjusted the slightly clunky up-shifts while the transmission and engine are still in warm-up mode. Most people report it only happens when the car isn't yet warmed-up.

Based on long experience with TCU updates in other sporty cars, it will be equally possible that they will screw-up a bunch of things that were better left alone. We need some knowledgeable people to dig into this before it is too late.

EDIT: Got too hopeful. Should have known KIA wouldn't get an update out in less than a year. The OP is undoubtedly dealing with TSB SA341:

Issue Number SA341 - Fast Static Gear Shift Logic Improvement (2.0 and 3.3GT)

 

[MerlintheMad]

The initial purpose was to add a proper manual mode to the transmission while in Sport--i.e., it won't revert to "D" when you come to a stop and it won't automatically up-shift when you approach the rev limiter. The programming the car came with is similar to what you would get in a minivan or econo-car.

I happen to appreciate the rev limiter. My first Launch Control experience hit the red line; my fault; I had forgotten that I was in manual gate, so when I pulled my foot off the brake the RPMs shot up over 6.5K in first gear before I realized it. The rev limiter (even in manual mode, thank Kia and God) upshifted at once to reduce the RPMs to a civilized level and saved my engine.

The GT1 has manual gate, which satisfies all the objections about Sport mode shifting. The trans never upshifts below the red line, not even when you tell it to in cruise control coming downhill, when CC has caused the trans to downshift (to 5th) to hold the car back at the cruise setting. If you want complete control, you have be in complete control and not tell the car to do things for you. Turn every automatic function OFF. Then drive it. How GT2 "shift by wire" handles Sport mode and the paddle shifters I don't know. But manual gate gives full functional control of the shifting to the driver (again, if it isn't overridden by CC or other "driver assist" programs).

 

[Doel]

I happen to appreciate the rev limiter. My first Launch Control experience hit the red line; my fault; I had forgotten that I was in manual gate, so when I pulled my foot off the brake the RPMs shot up over 6.5K in first gear before I realized it. The rev limiter (even in manual mode, thank Kia and God) upshifted at once to reduce the RPMs to a civilized level and saved my engine.

The GT1 has manual gate, which satisfies all the objections about Sport mode shifting. The trans never upshifts below the red line, not even when you tell it to in cruise control coming downhill, when CC has caused the trans to downshift (to 5th) to hold the car back at the cruise setting. If you want complete control, you have be in complete control and not tell the car to do things for you. Turn every automatic function OFF. Then drive it. How GT2 "shift by wire" handles Sport mode and the paddle shifters I don't know. But manual gate gives full functional control of the shifting to the driver (again, if it isn't overridden by CC or other "driver assist" programs).

So what you experienced wasn't the rev limiter, that's just the transmission shifting for you and that indicates even in manual mode that you don't have full control. The rev limiter is a device that throws the rods back once you hit red line, preventing you from over revving the engine. It won't shift, it'll just sit there and bounce off the rev limiter until you shift or take your foot off the throttle. If you ever hear cars rev and you hear "wwwuuuuuuuaaaaaAAAAAWAWAWAWAWAWAWA" that's the rev limiter. So even if the car didn't shift for you, you weren't in any danger of damaging the engine.

 

[MerlintheMad]

So what you experienced wasn't the rev limiter, that's just the transmission shifting for you and that indicates even in manual mode that you don't have full control. The rev limiter is a device that throws the rods back once you hit red line, preventing you from over revving the engine. It won't shift, it'll just sit there and bounce off the rev limiter until you shift or take your foot off the throttle. If you ever hear cars rev and you hear "wwwuuuuuuuaaaaaAAAAAWAWAWAWAWAWAWA" that's the rev limiter. So even if the car didn't shift for you, you weren't in any danger of damaging the engine.

Interesting. I recall feeling the acceleration stall and looking at the Tach and seeing the needle "bounce" into the red line area, and then drop c. halfway back and start to accelerate again at lower RPM, at which point I said "bag it, I screwed this up!" and lifted my foot off the gas. That doesn't quite match what you said, because I went past the red line. But it does sound like a very facile nanny safeguard. Whatever it is called, "it" yanked my engine out of first and dumped it into second or third at once, thus killing the over-revving that I was doing.

 

[Doel]

Interesting. I recall feeling the acceleration stall and looking at the Tach and seeing the needle "bounce" into the red line area, and then drop c. halfway back and start to accelerate again at lower RPM, at which point I said "bag it, I screwed this up!" and lifted my foot off the gas. That doesn't quite match what you said, because I went past the red line. But it does sound like a very facile nanny safeguard. Whatever it is called, "it" yanked my engine out of first and dumped it into second or third at once, thus killing the over-revving that I was doing.

I haven't hit redline in this car yet (break in period) but in my other cars the rev limiter is usually set a little after the red mark on the tach. What you're describing is definitely the car up shifting for you, if it was the rev limiter you would just be sitting there with it bouncing off it with no acceleration.

 

[St1nger Guy]

Does anyone notice when coasting, if you press the throttle again even slightly you get a little bump when it kicks the fuel back on?

I think a lot of what people are feeling with transmission has to do with the fuel cutoff when coasting. As long as your RPM's are above 1200 I believe it is and you are coasting there is 0 fuel being sent to the cylinders to keep the MPG's up. That's why when you cost it shifts down automatically to keep the RPM's above this limit. I noticed the 2019 has an option for neutral coasting which probably lets the car coast for a much longer time but with no fuel cutoff. My issue is its very noticeable when pressing the throttle after coasting that it's kicked back in. Might be due to all my mods creating too much freedom/bald eagles.

 

[MerlintheMad]

Does anyone notice when coasting, if you press the throttle again even slightly you get a little bump when it kicks the fuel back on?

You have a MY19? Because I wasn't aware that any US MY18s had the coast feature.

 

[St1nger Guy]

No mine is an 18. Got it in April.

 

[upsidedown]

Does anyone notice when coasting, if you press the throttle again even slightly you get a little bump when it kicks the fuel back on?
My issue is its very noticeable when pressing the throttle after coasting that it's kicked back in

Yes pretty crappy how it bumps as you say. I think it's somewhat better if you actually press the throttle further rather than feathering it. So either stay off the throttle or give it some

 

[St1nger Guy]

Glad I'm not the only one with the issue. My Optima SX did the same thing. Feels like there's play in the drivetrain that you take up when you press the gas.

 

[Marc Collins]

Glad I'm not the only one with the issue. My Optima SX did the same thing. Feels like there's play in the drivetrain that you take up when you press the gas.

Torque converter engaging and disengaging...and the more gears you have, the more noticeable it will be because depending on throttle application pressure the transmission decides it needs to shift a gear (or two) as well, which is half of the delay.

A) Sport mode eliminates this by keeping the car in a gear that is ready for action. Result=poorer fuel economy and more noise.

B) Even in Comfort, the car makes reasonable attempts to downshift as you are coasting down in speed. Result=people complain that the transmission is jerky (witness other threads here on that topic).

C) Name one modern/7-8 gears traditional automatic transmission that does not do this. Result=I don't think you can find one.

 

[Revvdmedia]

Torque converter engaging and disengaging...and the more gears you have, the more noticeable it will be because depending on throttle application pressure the transmission decides it needs to shift a gear (or two) as well, which is half of the delay.

A) Sport mode eliminates this by keeping the car in a gear that is ready for action. Result=poorer fuel economy and more noise.

B) Even in Comfort, the car makes reasonable attempts to downshift as you are coasting down in speed. Result=people complain that the transmission is jerky (witness other threads here on that topic).

C) Name one modern/7-8 gears traditional automatic transmission that does not do this. Result=I don't think you can find one.

I concur with torque converter lockup. I've noticed the "bump" in some shifts and after watching the tach, I'm certain it's abrupt torque converter lockup, not an actual gear change.

 

[MerlintheMad]

A) Sport mode eliminates this by keeping the car in a gear that is ready for action. Result=poorer fuel economy and more noise.

Interestingly, the manual gives a heads up if you are in Eco: you might hear increased engine noise. But when talking about Sport or Custom mode, the warning is only about lower fuel economy, not increased engine noise. I asked about this upon reading that, and one post said his former ride (a BMW, iirc) did the same thing. But it is counter intuitive to me that Eco, the purported mode for best average mpg, would also be the noiser drive mode. I actually cannot tell any difference between the engine sound in Sport or Eco.

 

[Marc Collins]

Interestingly, the manual gives a heads up if you are in Eco: you might hear increased engine noise. But when talking about Sport or Custom mode, the warning is only about lower fuel economy, not increased engine noise. I asked about this upon reading that, and one post said his former ride (a BMW, iirc) did the same thing. But it is counter intuitive to me that Eco, the purported mode for best average mpg, would also be the noiser drive mode. I actually cannot tell any difference between the engine sound in Sport or Eco.

Eco won't be noisier. It keeps revs low and shifts earlier. And, it uses the lowest setting for active (i.e., fake) engine noise. Lack of proofreading if the manual says that.