Hyundai Elantra GT banner
1 - 16 of 16 Posts

·
Registered
Joined
·
15 Posts
Discussion Starter · #1 ·
I don't know if it's supposed to be like this, but I notice after the transmission shifts into second and mostly third, there's a dead spot in acceleration for about half a second, then there's a small surge. It kinda makes the driving experience not terribly pleasant.
 

·
Registered
Joined
·
7 Posts
I’ve noticed something similar lately. I wonder if it’s our turbos not holding boost well between shifts?
 

·
Registered
Joined
·
8 Posts
I get this too. Like a flat spot. I was thinking it was the traction control or stabilitiy control, holding back on the throttle. I turned off both (long press the TC button) and it seemed like it may have stopped it as far as I cound tell. Could you all try this and post your result or have you already ruled this out?
 

·
Registered
Joined
·
132 Posts
I get this too. Like a flat spot. I was thinking it was the traction control or stabilitiy control, holding back on the throttle. I turned off both (long press the TC button) and it seemed like it may have stopped it as far as I cound tell. Could you all try this and post your result or have you already ruled this out?
Yeah if ESC or TC is on it will intervene and cause it. First thing I do is disable it when I start up.
 

·
Registered
Joined
·
7 Posts
Tested it over a couple of days and it feels significantly better with TC fully off. “Engine: on. Sport mode: on. Manual mode: engaged. TC: off” will be the new daily ritual I suppose.
 

·
Registered
Joined
·
25 Posts
Tested it over a couple of days and it feels significantly better with TC fully off. “Engine: on. Sport mode: on. Manual mode: engaged. TC: off” will be the new daily ritual I suppose.
Or your one of the unfortunate souls, like me, that has running issues that are impossible to diagnose. Keep your fingers crossed.

You can get a cheap Bluetooth obdII scanner to keep an eye on the boost. You may find that the boost is building as it should but you're just going nowhere for reasons that are unexplained
 

·
Registered
Joined
·
7 Posts
Hey, folks. I've already got over 12K on my 2020 GT N-Line (100+ miles per day). Here's what I've found...

Replaced OEM plugs and coil-overs with MSD coils and Bosch double iridium plugs. They really helped, but...

The tranny shifts into higher gears at or about 2.5K RPM, whether in Sport or normal mode. That means that just about the time the turbo spools up (c. 2K RPM) the stupid tranny shifts and you're back at 1.5K RPM, below the turbo actuation. Lags, spits, misfires.

So, the answer is leave it in manual mode and use the flappy paddles to shift at or above 3.5K RPM, the way God intended. That'll solve most of your problems.

Hope this helps.

-zed
 

·
Registered
Joined
·
25 Posts
I've tried this too, and the coils helped just a bit. I have been looking into the possibility that maybe I'm getting too much boost. I think reading the OBDii scans may be misleading without an analog boost gauge, which I'm thinking about installing...

HOWEVER, I decided to try closing down my plug gaps. I believe stock is .028. The lowest I've seen recommended is .025. I decided to see how it would act at .022. I gotta tell ya, it's been the only thing with a noticeable difference that I can actually quantify.
Watching the scanner, I notice that my fuel trims are always very high, especially when idling. Since I closed down the gaps, I've noticed my fuel trims drop significantly while idling, idling smoother, and on the highway, instead of being around +4 or +6, I'm actually hanging around 0 or even going negative. My fuel efficiency has increased as well where I usually get 31-33 on the highway I'm getting 35-37. ( I drive 250 miles a day sometimes)

Not sure if anyone else is gonna try this, but I'm gonna go lower this weekend because while it's significantly better, it's still not perfect.
 

·
Registered
Joined
·
7 Posts
Takeeon:

Not sure about the safety of narrower plug gaps. It is an aluminum block, after all... But, you may not be totally wrong either. After I pulled the OEM coil packs and NGK plugs, I saw evidence of arcing above the stem, a neat little burn just above where the plug meets the cylinder head on CYL #3.

For those with less inclination to mess with manufacturer's specs, at least try my driving setup, which yields nearly flawless results (I said 'nearly'):

1. Sport mode off, since you'll be shifting at whatever RPM you choose. Manual shifting in Sport mode has given undesirable results (misfires), for me.

2. ESC/TC on (cuz I gotta have cruise control and there's none with it turned off).

3. Shiftronic on (stick pulled to the left) and use either the shift lever to up- or down-shift (1st to 2nd gears on corners only, for me), or the flappy paddles (my preferred methodology).

4. And finally, never shift below 3.5K RPM, so you can stay in the turbo's power band! Personally, I never shift below 4K and frequently ~5K. I never redline the engine, cuz I want it to last awhile, y'know?

NOTE: Basically, what you're doing is 'dumbing down' the car by removing some crucial decisions the ECM and TCM are horribly, laughably mismanaging. If I weren't concerned about voiding my warranty (but I certainly am), I'd probably consider an actual custom tune (but, I'm not gonna cuzza the aforementioned) to make the danged thing work the way it oughtta.

As a final note: If you're in a low-leverage situation (e.g., residential driving, wide-open highways, etc.), the car's performance is perfectly acceptable in Sport mode (all it does is keep the revs up a little higher... kinda pointless, really, unless higher rev-sound equates to 'sporty' to you) and full-auto DCT mode... But, if you have to rapidly accelerate even moderately (1.5K cruise with sudden increase to 3.5 or 4K), you can expect a single- or multi-cylinder misfire and undriveable power loss that won't correct until you pull over, turn off the engine, open the door to discharge electrics and then restart like nothing ever happened. It's waaay stupid, and not in the good sense of the expression.

P.S.
My Fiesta ST was a banshee, but they don't sell 'em in the Americas anymore (all trucks and SUVs, gag/puke), so I got the GT N-Line with tech pkg as the nearest suitable replacement. It's a comfortable car, all the bells and whistles... but, it ain't comparable to the FiST for performance, by a long shot.

-zed
 

·
Registered
Joined
·
25 Posts
My symptoms slowly crept back in, but they're still not at bad as they were. After adjusting I reset the ECU. It runs pretty good for a few days until it finally gets around to testing the evap system, then things slowly creep back in.

When it's running well, there's not any need to to even get to 3.5k most of the time. The low end torque is excellent.

All that aside, my fuel trims are still looking good and this fuel economy is blowing my mind
 

·
Registered
Joined
·
7 Posts
Takeeon:

My daddy always used to say, "If you drive like an old lady, you'll end up with an old lady's' car."

Now, granted, the low-end torque's alright... until you put your foot down, even a little. Then -- on my specific vehicle, at least -- the engine sputters, misfires and becomes virtually undriveable until I limp over to the shoulder and do a complete 'cold reboot', as outlined in my previous post.

For anyone who'll consider my findings:

1. Less drivetrain computerization is required, not more. There's a seat-of-the-pants sport car in this thing and imma find it, even if it hairlips the Governor!

I'm about 95% there, right now; I just can't trash 'muscle cars' the way I used to in my 2,400 lb. FiST, cuz Inertia is a Universal Law and responsiveness/'suddenness' is all about weight-to-power ratio. I doubt we'll see any Ed Block or Pros vs Joes videos featuring a GT N-Line.
(NB: I also doubt I'll ever be able to approach the FiST's performance in the GT, without significant and costly engineering-level mods. The HGTN-L just weighs too much at 3,500 lbs. -- see, 'Universal Law', above -- with the same HP and torque as the FiST, but no factory-standard 30-sec turbo overboost to 230 HP/210 ft-lb; but it's fast enough to do all the things I need it to do, given the right driver. Meaning, me.)

2. I'm not saying you should drive the car aggressively at all times. Rather, that it should driven as aggressively as is prudent for longevity in the vehicle, whenever you get the chance -- like, when entering a highway or making a passing/overtaking maneuver.

My goal when driving is to get to my cruising speed (speed limit plus 10%, e.g., 77 in a 70) as rapidly as possible and then make as few adjustments to speed as practicable thereafter. It keeps the car running right... or, as right as possible given the apparent computer problems this manufacturer has throughout their lineup. Why pay for and drive a titular sport car, if all you really need is a squirrel-in-a-cage, 86 hp/56 ft-lb FWT putter-buggy?

3. On my 108-mile roundtrip daily commute, I always accelerate up to </= 6K RPMs (sub-7K-redline), but fewer than 7 occurrences, for 30 seconds or less each time, in my total 2 hour drive (i,e., between 2 and 3 total minutes of 'hard acceleration' over a 2-hour timeframe). The rest of the roundtrip, I'm chillin' in cruise, Normal mode and full-auto DCT, letting the computer do most of the highway cornering, pulling about 2.5K RPM and making 35-37 MPG, depending primarily on headwind/tailwind factor. And I'm doing that on mid-grade 91 octane.

ADVICE: Dumb the car down, as described in previous post. ...It's already too smart for its own good...

Parenthetically
-zed
 

·
Registered
Joined
·
7 Posts
Upon further review:
Turning off Electronic Skid Control
does virtually eliminate uneven acceleration. So now, I only turn it on when at cruising speed on the highway and in low-leverage situations, as described above, so I can use cruise control. Kind of a PitA, given that my Fiesta ST would do cruise control regardless the status of ESC.

...and why in the name of all that's holy would the ESC be so stingy? I could see it if the GT N-L had the HP/torque of a Veloster N or i30 N. 'Granny' overkill and no Hyundai-based solutions likely forthcoming for this discontinued model. Meh.
 

·
Registered
Joined
·
12 Posts
Upon further review:
Turning off Electronic Skid Control
does virtually eliminate uneven acceleration. So now, I only turn it on when at cruising speed on the highway and in low-leverage situations, as described above, so I can use cruise control. Kind of a PitA, given that my Fiesta ST would do cruise control regardless the status of ESC.

...and why in the name of all that's holy would the ESC be so stingy? I could see it if the GT N-L had the HP/torque of a Veloster N or i30 N. 'Granny' overkill and no Hyundai-based solutions likely forthcoming for this discontinued model. Meh.
Agreed, after reading this thread earlier, I started turning it off and it makes a big difference.

I own a 2018 Porsche Cayman GTS and I bought the N Line for my daily driver. Naturally I compared the Elantra to the Cayman and the Elantra paled in comparison. With our area getting cooler temps with approaching winter I pumped up the tires 3 psi over the recommended pressure and wasn’t I pleasantly surprised at how much better it handled. Less darty, more planted and more confidence inspiring in high speed cornering. Still no Porsche, but a great improvement.
 

·
Registered
Joined
·
7 Posts
Next thing to do is get Continental Extreme Contact all-season tires on it for about $1K, maybe lighter wheels too. Not keen on stock tires.
 
1 - 16 of 16 Posts
Top