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Crosspost - 2019 Veloster N misfire/fuel issue

Cygnus X-1

Well-Known Member
Jul 25, 2018
1,172
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US
Not happening on mine. Almost 2000 miles now. I will say that this could be an issue with the electrical system, due to poor ground quality.

This was a huge problem on the first gen VTs, causing all kinds of misfiring issues and ignition coil problems. What we did was clean the paint and primer off of the main (engine bay) chassis grounding points so bare metal was exposed.

This improves the electrical connections by lowering resistance and voltage drop. Use dielectric or any other conductive grease to seal the exposed metal to grounding plate connections.

Before doing this, use a multimeter to test the electrical resistance of the main chassis grounding points and you should see upwards of 6-12 ohms. After cleaning up each grounding point, test with the multimeter again and you should see a substantial reduction in resistance. They should be around 1.0 ohms or lower each.

Ignition coils rely on the chassis ground on the RH side strut tower (passenger side in LH drive vehicles), so test and clean that one first. The one on the LH side (connected to the negative battery terminal) is behind the ECM, so do that one later when you have more time. There are others scattered around the engine bay (including two right next to the ECM).

Once you finish, the engine should start easier and hopefully your misfiring issues will be cured.

If it does not fix the issue, then you can diagnose the HPFP with a dealer’s help.
 
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PcChip

Member
Mar 25, 2019
67
24
8
Dallas
I'd like to let everyone know that after I took two road trips (dallas->houston->dallas->san antonio->dallas) and now have 2250 miles, the issue appears to have gone away. No idea if it will come back or not.

When it was happening, one thing that seemed to help a bit was to start the car, let it idle for 10 seconds, turn it off for 5 seconds, then start it again and drive, it happened less when I did that.

and no, never any check engine lights or codes that the dealer could pull
 

RonnieB223

New Member
May 14, 2019
2
0
1
Kentucky, US
No lights showing is going to make this difficult. Just picked mine up and am around 350 miles, thought it seemed sluggish the last couple of days. Then again it's been around fifty degrees here. Hoping it's not going to be an issue....
 

PcChip

Member
Mar 25, 2019
67
24
8
Dallas
yeah mine sometimes feels sluggish and sometimes feels quick, at first I thought it was just because of air temperature, but it doesn't actually seem related. Can't put my finger on it
 

R Veloster N

Well-Known Member
Mar 5, 2019
4,910
3,750
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Rocky Mountains, US
I'm first going to have to ask, what modifications have you done to the Veloster N?

I can see by your user name you might be utilizing a Performance Chip possibly, might be wrong but if you are, remove it and throw it in the trash or send it back and get your money back. They are junk and a scam even proven by dyno's.

Second, what fuel are you running in the tank? Less than 91 is a big non-starter.

What mode are you running the car in?
 
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Crocoman

Well-Known Member
Dec 26, 2017
1,729
1,836
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Scotland
@R Veloster N what’s a ‘Performance chip’ if you don’t mind me asking?

To the OP, search the forum as a lot of us early I30N adopters had an issue with our ECU’s (requiring a replacement) and fuel pump. I don’t believe the VN suffered from this but who knows....

My I30N still has the very occasional hesitation on start up but no actual loss of power after I had my new ECU.

These turbo charged engines don’t like temperature extremes, that’s for sure. And it’s something I first noticed in my Kia Pro Ceed GT - she didn’t like the cold!

Of course, if you are concerned there’s perhaps an underlying issue then I’d get the car booked in.
 

R Veloster N

Well-Known Member
Mar 5, 2019
4,910
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Rocky Mountains, US
Stock, never heard of "performance chip", 93, N mode
Sounds like you've gotten some bad fuel (water in the fuel). Run some dry gas or FI cleaner thru the system ie, Chevron Techron, BG Fuel Cleaner etc.

Does it respond similarly in other modes; normal, eco, sport?

Has your N ever gone into limp mode during these issues?

Bad fuel will cause it to go into limp mode to stop any damage occurring to the motor.

Engine check light ever come on during these events?

Also, disconnect the battery for 30 minutes. This will cause the ECU reset to OEM setting. It will also cancel the limp mode. See if this doesn't solve the issue.

@R Veloster N what’s a ‘Performance chip’ if you don’t mind me asking?
A Performance Chip is a plug in ODB II chip that is suppose to make performance tuning changes to the ECU. https://www.chipyourcar.com/ This is just one of them. They're a scam and proven not to work by dyno. Many times, causing more problems to the motor.
 
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Crocoman

Well-Known Member
Dec 26, 2017
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Thanks for that. I know some tunes are loaded via a car’s OBD2 port so was just curious.

Definitely could be a fuelling issue and better to eliminate that first.
 
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R Veloster N

Well-Known Member
Mar 5, 2019
4,910
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Rocky Mountains, US
No problem, you're welcome and if you see one like it, don't be persuaded to buy it either.

Generally it's the simplest problem which causes such issues. Needs to be diagnosed correctly. Start with the simplest first and then go forward. It will saves time, effort and money.
 
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SAWKVN

New Member
Apr 19, 2019
7
1
3
Ohio
I think I'm having the same issue. The term bucking that OP used in the link above is exactly what I experience when the engine is cold.
 

PcChip

Member
Mar 25, 2019
67
24
8
Dallas
I think I'm having the same issue. The term bucking that OP used in the link above is exactly what I experience when the engine is cold.
It stopped happening to me once I passed about 2k miles. I never dropped it off at the dealership because it stopped happening before they were ready for me. They did try pulling codes though, there were none.
 

PcChip

Member
Mar 25, 2019
67
24
8
Dallas
I stopped replying to you earlier because you presume too much.
You presumed I was running a "performance chip"
You presumed I was running low octane fuel
You presumed I was running bad fuel with water in it (even though the other thread has several other people reporting the same problem - we all have watery gas?)
You now presume Sawkvn is running bad, low octane fuel.

This post is to raise awareness with other VN owners, which it has successfully done now that SAWKVN has replied.
 

R Veloster N

Well-Known Member
Mar 5, 2019
4,910
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Rocky Mountains, US
It's reasonable to say; You've raised no awareness!

You've stated you've had an engine miss, now it's gone @ 2K miles You didn't bother to respond to any of the questions put to you, for a possible diagnosis or give any explanation. It's only happened to you and one other possibly. Yours has disappeared so, this leaves one person. What awareness have you raised?

I presumed nothing, only asked questions in order to help diagnosis a possible problem. Which you chose to ignored and likely will again. At least I had the good sense to ask questions, in order to establish a baseline, for a some logical conclusions. Then offered up the simplest possible cause first.

The most likely problem is, the first as well as easiest too diagnosis. Try Occam's Razor on for size: Another way of saying; it is that the more assumptions you have to make, the more unlikely an explanation.
OR
Occam's razor or the law of simplicity. Occam's Razor instead is saying is, that when presented with competing hypotheses that make the same predictions, one should select the solution with the fewest assumptions and is not meant to filter out hypotheses that make different predictions.

There are members who own Veloster N's and haven't experience any of the same problems. You and the other individual are isolated cases, at best.

So the logical conclusion is the simplest; you gotten bad fuel, used to low an octane, have a fouled plug or..... You offered up nothing, nor did you take the time to diagnosis the issue at all. Did you use any logical or systematic diagnostic methods at all? Do you have a more simple or better explanation? By your own responses, no.

So, you say in the first post, "there's a problem and we could use more people talking about it, if it happens to you" and then you're attempting to stifle the discussion, you started. Oh brother, seriously!:rolleyes: And, the miss that you experienced, which was started by a crosspost from another forum, has magically disappeared "poof," with no explanation.:rolleyes:

Cygnus X-1; asked questions and made suggestions. Did you respond to his questions, attempt to utilize the suggestions or do anything he offered to diagnosis the issue?

Facts, don't care about your feelings. Neither do I. And I'm not going to argue with you, about your personal emotions or misunderstandings. Whew!
 
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Y0UKN0WITSCHRIS

Well-Known Member
Mar 6, 2018
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I think I'm having the same issue. The term bucking that OP used in the link above is exactly what I experience when the engine is cold.
The cold bucking is normal Hyundai quirks. My VT did it from new and also now my VN. As well as basically every Turbo Hyundai on our lots. Just take it easy when she’s first waking up in the morning and you’ll have no probs.
 
Jan 22, 2019
53
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England
The cold bucking is normal Hyundai quirks. My VT did it from new and also now my VN. As well as basically every Turbo Hyundai on our lots. Just take it easy when she’s first waking up in the morning and you’ll have no probs.
If this is the same problem I’m experiencing on my i30 N then it bucks in first and second from from anywhere between 1-3k revs. Can I take it easier than that?

At work I have to pull out into a third lane on what is almost a blind bend - this bucking has caused me problems here before.

What am I supposed to do at the end of the day? Sit in my car until the engine has warmed up?

That’s not a quirk, it’s a failure in design or engineering.
 

Y0UKN0WITSCHRIS

Well-Known Member
Mar 6, 2018
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If this is the same problem I’m experiencing on my i30 N then it bucks in first and second from from anywhere between 1-3k revs. Can I take it easier than that?

At work I have to pull out into a third lane on what is almost a blind bend - this bucking has caused me problems here before.

What am I supposed to do at the end of the day? Sit in my car until the engine has warmed up?

That’s not a quirk, it’s a failure in design or engineering.
That’s a little more severe than what I’m quoting. They act a little sluggish and buck a bit when they’re first warming up. But if you need to get up to speed you can. It just takes a lil longer with a lil more fight than if she was properly warmed up. But it has never caused me to fear for my safety or have to avoid the hammer lane.
 
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