• Welcome to N-cars.net - the largest Hyundai N car forum. Check out the model specific sections below and scroll down for country specific forums. Scroll down for i30 N, Ioniq 5 N, i20 N, Veloster N and Kona N forums! Check out the i30 N Bible Here!
On my last car I noticed more consumption during the winter. I think most of the blowby occured during warmup, before the rings expanded and got a good seal.
 
Quick question: is stuff like this covered under warranty? :oops:
Piston rings are a wear item, so likely not.

Back to the topic...

Reduce warmup idle periods to a minute or two, as putting load on the engine will get it to operating temperature faster. Obviously this depends on climate and ambient temperature, but really try to avoid this during the first few hundred miles.

Here is my preferred “burst method” break-in procedure (based on MotoMan):

If you are still early in your “break-in” period, drain, flush and refill the oiling system with a quality 0W-30 conventional oil having high molybdenum content (also swap oil filter, of course).

Before beginning, ensure that you have identified a location nearby and a timeframe where there is little to no traffic for safety purposes. Avoid places with lots of stoplights, i.e., try to use backroads if possible.

Once proper oil operating temperature is reached (you have a bulit-in oil temperature gauge, so no excuses), use hard to full throttle in 2nd gear (and 3rd if possible) across the RPM range and when you let off the throttle, decelerate using engine braking. Do three pulls to say 4500 RPM or so, drive normally for a minute then repeat to 5000, repeat to 6000, repeat to redline (6800). Park the car and let it cool down completely.

Repeat the overall process two more times and your break-in is essentially (~80-90%) done. Should take no more than 15-20 miles. Change oil & filter again, inspect the old oil for debris, continue driving a bit harder than normal and use lots of engine braking. Change oil anywhere from 200-1000 miles (you can do another short conventional round in between if you prefer) and then switch to true full synthetic oil with excellent wear resistance.

If you don’t want to use hard or full throttle, engine braking should still be your primary focus, as it puts plenty of load on the piston rings in order to force a good seal. You can vary the procedure to more closely follow the factory recommendations if you prefer, but in a much shorter timespan.

There are several other things that contribute to blow-by and fuel dilution, what I mentioned earlier is the foundational primary cause (poor break-in). Here are some general references that cover various post-break-in aspects:

https://www.bobistheoilguy.com/what-is-blow-by/

https://blog.amsoil.com/what-is-fuel-dilution-and-why-is-it-bad/

https://www.azom.com/article.aspx?ArticleID=16891
 
Last edited:
On a related note, if you run catch cans (a very good idea), understand that they are essentially “blow-by monitors.” Cans filling up quickly with oil, fuel and water indicate poor piston ring sealing. Cans that only catch small amounts of just oil or are dry indicate good to excellent piston ring sealing (provided the cans are installed correctly) with low to minimal blow-by.
 
Interesting stuff.
Why do you think that manufacturers recommend something completely different? especially when it is them that picks up the tab for a failed engine, and doubly especially when they offer a 5 year warranty?

Yes, piston rings could be considered a wear item, but everyone expects an engine purchased from a major manufacturer to last 5 years and for the manufacturer to repair it under warranty if it fails within that time.
 
Why do you think that manufacturers recommend something completely different? especially when it is them that picks up the tab for a failed engine, and doubly especially when they offer a 5 year warranty?

Yes, piston rings could be considered a wear item, but everyone expects an engine purchased from a major manufacturer to last 5 years and for the manufacturer to repair it under warranty if it fails within that time.
Lawyers tell them to do it. They don’t want people crashing by aggressive driving and it would be a huge liability risk to say “Drive it like ya stole it!” in the owners manual.

Many OEMs (BMW, for example) run the engines hard as soon as they come off the assembly line to get the piston ring sealing process started. It’s up to the owner to continue and finish it.

Yes, pistons rings are covered by the warranty regarding manufacturing defects, but what I meant is that blow-by and fuel dilution are not something that H will fix or even acknowledge. Good luck with that!

Not forcing anyone to follow my break-in method, just put it out there for open-minded folks that want more performance and a better-running, more efficient engine. Talk to any successful performance engine builder.
 
Last edited:
Lawyers tell them to do it. They don’t want people crashing by aggressive driving and it would be a huge liability risk to say “Drive it like ya stole it!” in the owners manual.

Many OEMs (BMW, for example) run the engines hard as soon as they come off the assembly line to get the piston ring sealing procrss started. It’s up to the owner to continue and finish it.

Yes, pistons rings are covered by the warranty regarding manufacturing defects, but what I meant is that blow-by and fuel dilution are not something that H will fix or even acknowledge. Good luck with that!

Not forcing anyone to follow my break-in method, just put it out there for open-minded folks that want more performance and a better-running, more efficient engine. Talk to any successful performance engine builder.

I do understand what you are saying and do acknowledge this is a valid school of thought on engine break-in. Performance engine builders will generally build an engine like a shooting star.
"The light that burns twice as bright burns half as long, and you have burned so very very brightly Roy." Eldon Tyrell. :cool:
Hyundai have to engineer their engines (and other components) to last way longer than typical performance engine builders. Note: typical not all. :rolleyes:
Maybe this is why they use the gently, gently approach to engine break-in.
 
Gotta love an original Blade Runner reference... No, really, as long as you are doing it in a controlled and non-abusive manner, any engine that is broken-in aggressively for minimal blow-by will last longer and have fewer problems than the factory babying method, strictly because the rings are more evenly/thoroughly seated due to more heat and force. Simple physics.

Break-in is just the beginning. You still have to maintain the engine properly with quality oil/fuel/plugs and keep the internals clean.

What’s interesting is a VNPP arrived at a semi-local dealer with 19 miles on it, which I balked at. Perhaps they are doing a more aggressive break-in proactively, but I prefer to do it myself.
 
One could also have leakdown and compression tests done to get a better idea of how efficiently the engine is operating, for each individual cylinder, no less.
 
Last edited:
Was at another dealership today to ask about the problem and they told me that it's most likely the cold weather and the fact that the engine might be too cold for the first few minutes of the drive for the piston rings to produce a proper seal. I should however continue to check the oil level, just in case.
 
Given the very low mileage one owner indicates maybe they are spending too much time idling the car to "warm it up" allowing fuel to wash down the cylinder walls and find its way into the oil pan. The first 5-10 minutes of driving I have noticed the fuel economy is very poor when compared to when the engine is up to normal operating temps. The ECU is most likely reacting to colder conditions and increasing the fuel to the cylinders under these conditions. This used to happen regularly back when dinosaurs ruled the earth and we used manual choke valves to richen the air / fuel ratio for cold starts. Users would "forget" to push the choke knob back in after the engine had warmed a bit and resulted in diluted oil or at least oil that had a petrol (gasoline) smell. :rolleyes:
As for the owner with 30k kms on the clock. That is 3 years of average motoring. Maybe you should start a thread to see who has the highest mileage so far. You may win. :D i30n taxi perhaps.
Hahaha yeh maybe i have the most mileage, got mine over a year ago now. Did quite a lot of road trip last summer, and I do take it to work once or twice a week, which is a round trip of 120km...so it adds up real quick, but the car runs still strong beside that fuel smell in the oil.
 
My query was aimed at the OP's statement "As this is a direct injection car, it is normal to have some fuel contamination in the oil", I thought you were answering that rather than making a general observation.

@Kage79 surely the compression by the piston prior to sparking far exceeds the increased pressure of the directly injected fuel compared to normal induction? Even though the fuel is at very high pressure it's effect on the volume in the cylinder must be low? Happy to be educated here.
<iframe width="560" height="315" src="
" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

Did more research and this guys explains it way better than I could.
 
He doesn't explain it at all. He makes a statement, but doesn't back it up.

Basically "GDI engines are more susceptible to oil dilution, but the vehicle manufacturers and the oil manufacturers are aware of it, and so by carefully defining the oil grade and the service interval they reduce the effects to a minimal level that can be ignored under normal driving circumstances".

But no explanation as to why GDI engines are more susceptible.
 
  • Like
Reactions: stig_3754
Sounds like we need a medium to high octane fuel with sufficient detergents. Possibly a catch can type device, with low oil change intervals (probably most important) on a possibly higher grade of oil than required. Shortest amount of time spent letting the engine warm up without running it hard prior to reaching operating temperature and (at a minimum) weekly extended mile trips to get everything fully up to temp (if you normally have short trips).
 
Last edited:
Sounds like we need a medium to high octane fuel with sufficient detergents. Possibly a catch can type device, with low oil change intervals (probably most important) on a possibly higher grade of oil than required. Shortest amount of time spent letting the engine warm up without running it hard prior to reaching operating temperature and (at a minimum) weekly extended mile trips to get everything fully up to temp (if you normally have short trips).
That just about covers it . :cool::)
 
  • Like
Reactions: GazmaN
Why do you think that manufacturers recommend something completely different? especially when it is them that picks up the tab for a failed engine, and doubly especially when they offer a 5 year warranty?
New tires are coated with some sort of lubricant (which is coming from the manufacturing process inevitably) and that makes the tires slippery. The coating will be completely gone within 10km of hard driving (i.e. track hard) but with easy driving, some of those will be stay intact even after 100-200 km of driving. Same goes for the brake pads/rotors. It needs 10-20km of hard driving or 300-500km of easy driving to completely eradicate the initial slipperiness.

This is usually not a big issue for a car, since increased braking distance by (something like) 25% or lower lateral acceleration by 20% don't make a meaningful difference on a slowly driven car. However, recommending a hard driving is still not a good idea, since both increased braking distance and lower cornering capability will become prominent when it's being driven hard, and if customer crashes while following a recommendation, the manufacturer who officially recommended a hard driving might be liable to some degree at court (also you can't really promote an illegal activity as a company and a hard driving on public roads usually equate to an illegal activity).

However, this is a serious issue for motorcycles, since slippery tires could make you crash immediately if you lean too hard, or even make you fly away (i.e. highside) if you're a bit too hard on throttle while leaning. I believe this is the prime reason why they recommends the easy riding when it's new. Engine longevity doesn't matter much on motorcycles anyway, since motorcycle engines do not last long in the first place and most manufacturers give you only 1-2 years warranty on the engines of sport bikes (even shorter for dirt bikes, 0-30 days in many cases) and you can't really ride the sport bikes much within that 1-2 years (unless that's your only mode of transportation). Some manufacturers even go further and limit the RPM during the initial period (e.g. S1000RR and HP4 are limited at 9k RPM before the first 1,000km service), but I think that's a bit extreme precautionary measure.

Anyway, I'm not sure whether the Motoman's method delivers any better results on modern car engines. I think it might be capable of delivering better results on a dirt bike with an air cooled, single cylinder engine, but for car engines? I'm not sure because of the following reason.

I've bought about 30 new cars between 2005-2015. I've often bought the same car twice (usually pre-FL and post-FL) and tried various break-in methods on multiple occasions. I've also tested the cylinder pressure of almost every my cars after the initial 500-1500km. But there was no measurable difference in terms of the cylinder pressure regardless of how they were driven on the initial 500-1500km. Same goes for the power. Although I've dynoed only some of those cars, but the results weren't consistent at all.

My conclusion from my 10 years long experience/experiment was, even if you drive the car very hard from the beginning, it doesn't make any difference in terms of power or the cylinder pressure. It's not better nor worse. It's just same. So, as a man with zero patience, I've opted for no special break-in, other than 5-10 times of hard engine braking. I just drove them normally (but mind that my normal driving is bad enough driving to be locked up in a jail if you're doing the same in the US/Europe and failed to getaway from police).
 
Fair enough, which is why I’ll wait for a VN with as few miles as possible, immediately have the oil swapped to conventional, do the method for 25 miles, swap and inspect oil, run for 500 miles, swap oil to true full synthetic, get it dyno’d and compare to other graphs and factory numbers.
 
He doesn't explain it at all. He makes a statement, but doesn't back it up.

Basically "GDI engines are more susceptible to oil dilution, but the vehicle manufacturers and the oil manufacturers are aware of it, and so by carefully defining the oil grade and the service interval they reduce the effects to a minimal level that can be ignored under normal driving circumstances".

But no explanation as to why GDI engines are more susceptible.
From Amsoil website:
"The major side-effect of this technology is the increased risk of fuel dilution. As fuel is sprayed into the combustion chamber, it can wash past the rings and down the cylinder walls, into the oil sump."

source: https://www.amsoil.com/newsstand/articles/the-effects-of-turbochargers-and-gdi/
 
This is the official run in card for the I30N. Don't forget it's Hyundai that will be paying for your warranty repair jobs, not people on the internet. Adhere to what Hyundai say and you should have no worries.

There's a LOT more vehicle components that need breaking in than just the piston rings (which are pretty much already broken in anyway from factory).

Put it this way, if the rings were not broken in from factory half of all the engines Hyundai produce would be going back to the factory. Car manufacturers would never leave it up to the common consumer to break in an engine from scratch.

break.jpg
 
  • Like
Reactions: speedking