G2 Bucking under heavy acceleration

[penga25]

I wanted to check with other members if this is something others experience, (maybe due to the 8sp transmission)

when ever i floor it from either a stop or highway speed (passing, etc) the car accelerates in whatever gear it is but has a violent jerk when switching to the next gear. probably around 6k rpm. is the transmission confused? slow? or should this not happen

if it matters, 2016 ultimate 3.8 RWD model

 

[Alwaysforward]

Take it to the dealer. Test drive similar model (3.8 V6 Ultimate) to see if it acts the same with the service rep with you in both cars. Sounds like a tranny issue.

 

[smirn0ff]

I have 3.8 AWD and I am flooring often.
there is no bucking on my car, the gears changing smooth

 

[celltech]

No bucking while flooring it in my 5.0, but I will say there is some driveline lash when at low (under 20 mph maybe?) speeds and light on/off throttle applications. I also notice what seems like a lot of engine braking when gently slowing down and hitting the downshift points. I am not sure if it's related to DI or not...it just feels "strange" to me.

 

[srobak]

I also notice what seems like a lot of engine braking when gently slowing down and hitting the downshift points. I am not sure if it's related to DI or not...it just feels "strange" to me.

Are you in SPORT mode? That's when I see it on my 3.8. Otherwise - I only feel engine braking when it goes into 2nd, just like on my Azera.

 

[celltech]

Are you in SPORT mode? That's when I see it on my 3.8. Otherwise - I only feel engine braking when it goes into 2nd, just like on my Azera.

I would LOVE to keep it in sport all the time, but it won't shift into 8th until 80+...so I just leave it in normal.

 

[PinkFloyd]

I would LOVE to keep it in sport all the time, but it won't shift into 8th until 80+...so I just leave it in normal.

I'll put it in sport every so often for fun, but I'm liking the 5.0 character pretty well in normal.

No bucking thus far.

 

[TroyK]

I would LOVE to keep it in sport all the time, but it won't shift into 8th until 80+...so I just leave it in normal.

I found your statement interesting so I tested my car on the way home from work this morning. I was in sport mode, and the transmission shifted into 8th at 45 mph.

 

[danygenesis]

I found your statement interesting so I tested my car on the way home from work this morning. I was in sport mode, and the transmission shifted into 8th at 45 mph.

Mine won't go up to 8th until the car gets more than 70 MPH in Sport mode

 

[jaxsully]

Yes I had this same situation with a brand newa G2 5.0 Ultimate. Took it to the dealer and it took them 3 days to figure the problem out. It has to do with the fuel delivery system, they replaced some fuel delivery lines and all was fine.

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[srobak]

I found your statement interesting so I tested my car on the way home from work this morning. I was in sport mode, and the transmission shifted into 8th at 45 mph.

If you count them again - that will probably be 7th if under light acceleration, and only 6th if under moderate acceleration. I agree that 8th is only hitting at high speeds.

 

[TroyK]

If you count them again - that will probably be 7th if under light acceleration, and only 6th if under moderate acceleration. I agree that 8th is only hitting at high speeds.

apparently flipping from normal to sport at 45-50 mph doesn't tell the whole story. this morning i was out on a local highway and indeed at 55 to 60 the tranny was reluctant to shift into 8th while in sport mode. however, when i engaged the cruise at 60 mph, it shifted right up into 8th (yes i was still in sport mode). i find that interesting!

 

[smirn0ff]

Sport mode is shifting to 8th in low speeds.
When you are racing the car it will not shift to 8th for sure!

 

[penga25]

so i brought my car into Hyundai to look at this problem, they said the tech drove it and said it perfectly normal operation for the car. i told them that's a bunch of BS but it got me no where. according to Action Hyundai in NJ, when accelerating the car will hit the fuel cut off (about 6k RPM in my car apparently) in any gear and force the driver to let go of the gas so the car can shift.... what are my options here? i got this car out of state but use this dealer as "my" service center. are they just not wanting to deal with the car since they didn't make money on me for it? I've never driven a car in my life where its "normal" to not be able to hit the gas enough to pass another car without having to creatively apply throttle.

again, does anyone else see this as normal behavior for this car?

 

[jsmit86]

so i brought my car into Hyundai to look at this problem, they said the tech drove it and said it perfectly normal operation for the car. i told them that's a bunch of BS but it got me no where. according to Action Hyundai in NJ, when accelerating the car will hit the fuel cut off (about 6k RPM in my car apparently) in any gear and force the driver to let go of the gas so the car can shift.... what are my options here? i got this car out of state but use this dealer as "my" service center. are they just not wanting to deal with the car since they didn't make money on me for it? I've never driven a car in my life where its "normal" to not be able to hit the gas enough to pass another car without having to creatively apply throttle.

again, does anyone else see this as normal behavior for this car?

It's not normal. Ask to drive one or more from their stock. Also - see the post in this thread about the same issue being causes by fuel delivery. I have seen a few examples of this in the forum. IIRC, it was caused by defective fuel rails? If you don't get satisfaction, send an email to Dave Zuchowski. (Search the forum for the email address) Good luck. Don't give up.. the car is excellent once you get any of these issues remedied.

 

[xsolara]

Best to go on a test drive WITH the service tech with you. .... show him what it does when you are driving.
This way they can't say it's normal. If he still says it's normal go directly to Hyundai and register a complaint and get a file #

 

[Silverhare]

No bucking while flooring it in my 5.0, but I will say there is some driveline lash when at low (under 20 mph maybe?) speeds and light on/off throttle applications. I also notice what seems like a lot of engine braking when gently slowing down and hitting the downshift points. I am not sure if it's related to DI or not...it just feels "strange" to me.

I know this is an old post but I just got a 2018 G80 5.0 and mine is doing the exact same thing as you described. Did you ever find out what was wrong with it?
Mine is currently at the dealership.

TIA