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Technical bulletin for misfire/high pressure fuel pump

Jack_Red

Member
Jan 22, 2018
36
31
18
28
England
very frustrating, i can already tell im going to have to go through that whole process with the dealer which im not looking forward too. its going to be a pain getting this sorted
 

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Active Member
Nthusiast
Nov 5, 2018
125
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Poland
Give me your VIN if you want. I can check in Hyundai base if your car is subject to some repair campaign.
 

Cygnus X-1

Well-Known Member
Jul 25, 2018
1,172
1,556
113
US
Frankly I’m surprised your dealer did not know about the common issue with ECM & high pressure fuel pump (HPFP), as I believe there is a TSB and they should’ve checked the car’s history.
 
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Jack_Red

Member
Jan 22, 2018
36
31
18
28
England
It's currently happening again now, I'll be ringing the dealer the moment they open and expect them to pick it up from my office and drop a courtesy car off.
 
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Markvp1978

Active Member
Nthusiast
Jan 31, 2018
124
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I was wondering, because somerimes mine hesitates in 3rd or 4th when I floor it. Mine is from April 18
 

Alby

New Member
Feb 5, 2018
9
4
3
28
Hi, I've had my car back for a few days after having the fuel pump and ECU replaced. The dealership was fantastic, they admitted it was a known fault, organised a courtesy car as it was going to take them nearly two weeks to get the parts and even said it wasn't the first time they'd done this replacement at their site.

Anyway, that aside, since I've got it back I can't say I'm overly happy. I've seen other posts saying there's no turbo boost but I can see my turbo boost light coming on and hear the turbo winding up so that's not a problem. But despite this it just seems to be lacking some guts. It is almost as if it's lost say 20 to 40 BHP. Don't get me wrong, it's still quick but lacks that aggression, that little something that makes you smile. I've noticed it more when I've been in 6th gear on the motorway doing 60/65 behind a lorry and put my foot down a bit for an overtake. I never used to consider coming out of 6th but now feel that 5th would be a better choice because 6th is just taking forever to pick up that extra 5-10mph. I've also noticed it's not absolutely smooth on tickover. Just now and again it's blipping a tiny amount which I'm sure it never used to do.

I was wondering if anyone else has had these issues?

And has anyone who's had the fuel pump / ECU replaced actually managed to get the car tested to see if it's still got all 270 ponies under the bonnet?

I'd also be interested to see the BHP and torque mappings on the old and new ECUs If anyone has got hold of them from Hyundai etc. Because I'm convinced the power delivery is noticeably different to how it was prior to the new ECU / fuel pump.
Why would you overtake in 6th gear? That's called lugging the engine ya noob
 

R Veloster N

Well-Known Member
Nthusiast
Mar 5, 2019
6,967
5,023
113
Rocky Mountains, US
Excuse my ignorance but where's the reference to a Hyundai TSB for fuel pump replacement? If there is one, it's will be easy to find and post.
Why would you overtake in 6th gear? That's called lugging the engine ya noob
Not really, this engine pulls strong and smartly from 60 in 6th gear and you're not lugging it either.
 
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Tom Vanlimbergen

Well-Known Member
Nthusiast
Jan 19, 2018
575
689
93
47
Just ran in to my first problem with the N, resembles the highpressurepump issue a bit.
On tuesday, during a highwaytrip on cruisecontrol, the car started jerking. Went of the highway, but the car was hardly driveable at constant speeds. No lights on the dash and no error on the screen. Drove to the dealer and they found a faultcode: misfiring on cylinder 2. By then he was even misfiring on idle. Strangely enough the exhaustvalve went wide open, no matter what setting.
It was late allready, so the dealer tried to solve it by putting another ignitioncoil in from an N he had for sale. He gave me an apointment to bring the car in today. The other coil didn't help, symptoms stayed the same...
Didn't drive the car for two days and took it to the dealer this morning. The jerky drive was completely gone and the misfiring on idle was hardly noticeable. The exhaustvalve was behaving itself. When I put my foot down, the car accelerated but it hesitated twice in a full pull in third. On the performancediagram on the screen it only showed 240ish bhp, where it normally runs till 280.
The dealer told me they would have a look.
Got a call this afternoon that I could pick it up.
On collection the dealer told me it was misfiring on cylinder 1 and 2. They contacted Hyundai who told them to switch the coilpacks between 1,2 and 3,4 to see if that would help. Strange way of thinking when you know that changing the coilpack on cylinder 1 only made it misfire on 1 and 2 now.
Dealer told me to give it a try and come back if it wasn't fixed.
I drove of and was back in 10 minutes. On the first pull it was immediatly clear the problem was still there. Only difference is that it's less noticeable and the car is driveable now.
Dealer said he would contact Hyundai on monday and call me back. Told me I could keep on driving the car.
To resume: they haven't got a clue!
I'm thinking injectors or ecu.
Hope they get it solved quickly. Don't fancy driving around with a crippled car during the Christmasperiod (dealer is on vacation for two weeks).
N is a 05/2018 car, 46000km on the clock, no recalls needed, starts pretty good but sometimes a little hesitation.
 
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Davo01

Well-Known Member
Nthusiast
Jan 28, 2019
432
547
93
South Australia
Took the car into the Hyundai garage this morning. With a cold start, it would not go faster than 100km/h on the highway, I was seriously concerned that I would not make it.

I then watched the car spluttering as the technician drove it in to the workshop. Just had a call saying that the computer doesn't have any fault codes, so they cannot do anything. Any further investigation without a fault code would not be covered under the warranty.

I just sent them a copy of the video that I made yesterday.

@Moritz do you have any links to forums where others have reported this issue?
Lol. Typical. No black box telling them what to do, so can’t fix. Whatever happened to actual knowing one’s job?
 
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Mightymoo

Well-Known Member
Nthusiast
Sep 20, 2018
650
1,180
93
Norway
I’d think


Clever little thing. Interesting that they say you can still drive it but at low speeds. I’m not sure I’d be using it all.

Easy fix by the looks of it though. You’ll be desperate to get the car back in top shape Garth...
Agree.

You should get a free rental. Does not sound to smart to drive your car...
 

Jammin

Member
Nthusiast
Jan 26, 2018
95
96
18
41
Lol. Typical. No black box telling them what to do, so can’t fix. Whatever happened to actual knowing one’s job?
This is becoming more of a problem in general, there are very few mechanics who have any idea how to troubleshoot. Those that do are very sought after.
 
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R Veloster N

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Mar 5, 2019
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Rocky Mountains, US
There is Now a recall for gen 2 N due the fuel pump
Please share where, or atleast post the recall. No one has seen it, obviously.:) Still haven't seen a TSB, as referenced in the op's thread title either?

It's not vacuum (air) related, so it leaves electrical and fuel systems as the possible culprits.

Leaky Fuel Injectors possibly?;) If a fuel injector was failing, you will have running and performance issues. Partially clogged FI's, will also cause such issues.

The high pressure FI pump runs off the camshafts. If it was malfunctioning or failing owners would know it almost immediately and it's not going to get any better as it fails. So, it would be a persistent problem, not one that is off and on. Bad enough, the ECU will send the car into limp mode. I take it that it hasn't done so as of yet?

Electrical problems are on and off propositions. If you have a; bad coil pack, or engine, ECU, electrical system ground, this might cause such an intermittent problem. Checking the electrical system grounds, is one thing a technician needs to automatically accomplish. If its throwing a fault code for a failing coil pack, you simply replace it with a new one. Then send the faulty coil pack to the Hyundai engineers to find out what the coil pack failure is related to.

If it's ECU related; a simple reflash of the OEM software mapping will tell them directly. This is all semantics and should be done automatically by a competent service department and their technicians staff.

One thing you can do is; data log from the OBD II port. Data loggers are inexpensive and easy to install. This is a direct link to the ECU's functions. You might find fault codes being thrown, fuel pressure is being disrupted, voltage drops, etc. This would give the technicians something tangible to look at and help them diagnosis the possible issue/s.

Right now they're guessing and never solve the issues, unless they get lucky!
 
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Jan 22, 2019
53
36
18
England
Mine is in right now having the high pressure fuel pump replaced (or it will be when the parts arrive - they’re on back order) although after reading this thread I’m not convinced the issue is going to be solved.

I have some but not all symptoms listed by others. In 1st or 2nd under acceleration the car can severely jerk/buck. If I change up and continue accelerating the jerk/bucking seems to stop. Not noticed a problem in any other gear or speed. It’s only intermittent and all but one of the times have been cold starts. The bucking is to the point where I’m actually being thrown back and forth in the seat.

Didn’t have much hope that they’d do anything about it as it’s not happening all the time and they would need to see it but the technician managed to replicate it. I only mentioned it at the first service a few weeks ago. After investigation work they’re blaming the pump.

They mentioned nothing about a recall or ECU issues - only that Hyundai are covering the replacement under warranty at a supposed cost of around £2.5k. A colleague at work who knows far about cars than me mentioned coil packs to me and I mentioned this to the tech originally but he didn’t get much of a response to that specific suggestion to know if it factored into the troubleshooting they did. (FWIW, I’m not bashing the tech here. He seems great - he was the same that sorted out the speed info display and some other stuff without any qualms).

Didn’t mention about any of the things in this thread as all this happened prior to stumbling across it.

I’ll keep you all updated once I get the car back.

Edit: Not sure of the build date but car was delivered to dealership/first registered November 2018 I think. It has the square fuel cap.
 
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Tom Vanlimbergen

Well-Known Member
Nthusiast
Jan 19, 2018
575
689
93
47
Just ran in to my first problem with the N, resembles the highpressurepump issue a bit.
On tuesday, during a highwaytrip on cruisecontrol, the car started jerking. Went of the highway, but the car was hardly driveable at constant speeds. No lights on the dash and no error on the screen. Drove to the dealer and they found a faultcode: misfiring on cylinder 2. By then he was even misfiring on idle. Strangely enough the exhaustvalve went wide open, no matter what setting.
It was late allready, so the dealer tried to solve it by putting another ignitioncoil in from an N he had for sale. He gave me an apointment to bring the car in today. The other coil didn't help, symptoms stayed the same...
Didn't drive the car for two days and took it to the dealer this morning. The jerky drive was completely gone and the misfiring on idle was hardly noticeable. The exhaustvalve was behaving itself. When I put my foot down, the car accelerated but it hesitated twice in a full pull in third. On the performancediagram on the screen it only showed 240ish bhp, where it normally runs till 280.
The dealer told me they would have a look.
Got a call this afternoon that I could pick it up.
On collection the dealer told me it was misfiring on cylinder 1 and 2. They contacted Hyundai who told them to switch the coilpacks between 1,2 and 3,4 to see if that would help. Strange way of thinking when you know that changing the coilpack on cylinder 1 only made it misfire on 1 and 2 now.
Dealer told me to give it a try and come back if it wasn't fixed.
I drove of and was back in 10 minutes. On the first pull it was immediatly clear the problem was still there. Only difference is that it's less noticeable and the car is driveable now.
Dealer said he would contact Hyundai on monday and call me back. Told me I could keep on driving the car.
To resume: they haven't got a clue!
I'm thinking injectors or ecu.
Hope they get it solved quickly. Don't fancy driving around with a crippled car during the Christmasperiod (dealer is on vacation for two weeks).
N is a 05/2018 car, 46000km on the clock, no recalls needed, starts pretty good but sometimes a little hesitation.
Hyundai rang me up on thuesday and asked me to bring the car in yesterday. Hyundai Belgium told them to change all four fuelinjectors (has apparently been done to another Belgian N before). I was a bit sceptic because the car started pretty good, only every now and then a slight hesitation, nothing special.
Picked the car up yesterday evening and did a 150 km drive. Everything seemed to be ok again: the jerky driving at constant speed was gone, no hesitations when making full pulls, only thing that was still a bit strange was the idle. The misfires were gone but it was hunting up and down a little bit. O, and strangly enough: the stop - start wouldn't work. Normally that takes not more than a second to engage or to show the orange light, now it kept thinking for about 10 seconds and than showed the orange light every time. I took the car for a drive for work today of about 120 km and every time I stopped, the time the car needed to engage start-stop got shorter (and engaged) and idle became more stable.
After a while I must say everything is back to normal: normal power, smooth driving at constant speed, no hesitation, ...
Must be somekind of selflearning mechanism in the ecu.
So for me 4 new injectors seem to have done the trick.
Great service from the dealer also: they rang me up around noon today to ask me if everything was ok now because they were closing for two weeks and so I could still get a courtesycar if needed.
 

Patrick

New Member
Jan 30, 2020
2
5
3
Stevenage, UK
Hello everyone, so seems like I'm yet another person affected by same issue. Normal drive, sudden loss of power, misfires etc. Car got recovered yesterday, missfire on cylinder 3 detected and taken to the nearest dealership. FYI 28k miles on the clock, so this car is used daily and heavily during weekends (wink wink). Now I'm waiting for more info, but already been told in advance that "it will take some time" as they're busy and struggle with fitting my car in. I really hope this can be sorted as per post above and wont take long... This however encouraged me to join here, so would like to use this opportunity to say hello to all.
 

R Veloster N

Well-Known Member
Nthusiast
Mar 5, 2019
6,967
5,023
113
Rocky Mountains, US
Hyundai rang me up on thuesday and asked me to bring the car in yesterday. Hyundai Belgium told them to change all four fuelinjectors (has apparently been done to another Belgian N before). I was a bit sceptic because the car started pretty good, only every now and then a slight hesitation, nothing special.
Picked the car up yesterday evening and did a 150 km drive. Everything seemed to be ok again: the jerky driving at constant speed was gone, no hesitations when making full pulls, only thing that was still a bit strange was the idle. The misfires were gone but it was hunting up and down a little bit. O, and strangly enough: the stop - start wouldn't work. Normally that takes not more than a second to engage or to show the orange light, now it kept thinking for about 10 seconds and than showed the orange light every time. I took the car for a drive for work today of about 120 km and every time I stopped, the time the car needed to engage start-stop got shorter (and engaged) and idle became more stable.
After a while I must say everything is back to normal: normal power, smooth driving at constant speed, no hesitation, ...
Must be somekind of selflearning mechanism in the ecu.
So for me 4 new injectors seem to have done the trick.
Great service from the dealer also: they rang me up around noon today to ask me if everything was ok now because they were closing for two weeks and so I could still get a courtesy car if needed.
This seems to be the consensus amongst those who have had to had the problem in both the VN andi30N. I hope and expect @Y0UKN0WITSCHRIS to horn in here. He had it done a month ago and it solved his problems.
 
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watto33

Active Member
Jan 30, 2019
129
103
43
Brisbane
I really hope this becomes a TSB so we all have the right to get this done. My 2018 N with 20k's on the clock has not had a issue yet.

I wonder why some are fine and some aren't ? If the high pressure pump is not adequate why does it work find on other N's ?