Crawling in first gear at idle RPM

Combustion chamber swirl at idle is less ideal than any other point in the RPM range. This causes more fuel to be deposited on the cylinder wall and absorbed into the oil instead of held in suspension, and it also causes a burn with more soot, and the soot is more likely to deposit on the back of valves when they are open and the mixture is passing by them (not passing through the port but rather swirling past the open valve head).


It's really not much different than just idling the car. Extended idle followed by aggressive throttle is one of the LSPI triggers though (because of the cylinder wall fuel loading) so when you get moving again ease into it and don't dart off under full boost immediately.



It's probably fine though overall other than the risk of stalling the car. I mean, it's really no different than creeping with an automatic transmission car as far as engine loading goes. If you drive like this a lot (daily traffic jams) you should be doing the 3K mile oil service schedule.

The amount of misinformation in this thread is beginning to get a bit silly. This ^ is not correct. It's defined simply a detonation or knock, in every car.

LSPI is caused by droplets or particles in the combustion chamber—combinations of fuel and oil—that ignite prior to spark, resulting in uncontrolled, abnormal combustion. This creates spikes in engine pressure, ultimately causing internal engine damage.

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We don't have this problem with the Hyundai VN engine. The ECU software is programmed to spray additional cooling fuel at the point where LSPI generally occurs. Our engines and ECU's are equipped with; upgraded knock sensing software, LSPI software and a limp mode if knock is detected.

This happens far more with older turbocharged or NA engines running lower grades of fuel. Keep to what the engine is designed for and that's 91 Octane plus and there will be no such problems.

You may load up the piston tops and intake valves quicker with carbon from blowby but LSPI (detonation or knock) is not an issue with this engine at high or low speeds.

RedVN said:

The amount of misinformation in this thread is beginning to get a bit silly. This ^ is not correct. It's defined simply a detonation or knock, in every car.

We don't have this problem with the Hyundai VN engine. The ECU software is programmed to spray additional cooling fuel at the point where LSPI generally occurs . .Our engines are equipped with; upgraded knock sensing software, LSPI software and a limp mode if knock is detected.

This happens far more with older turbocharged or NA engines running lower grades of fuel. Keep to what the engine is designed for and that's 91 Octane plus and there will be no such problems.

You may load up the piston tops and intake valves quicker with carbon from blowby but LSPI (detonation or knock) is not an issue with this engine at high or low speeds.

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Why do you think it's misinformation? What you've replied with seems to be unrelated. Knock and detonation (spark knock) are spark related phenomenon. I made no reference to spark or ignition timing anywhere in my post. I was solely referring to pre-ignition caused by fuel and oil mixing on the cylinder walls under prolonged low speed/low load conditions (which is then put into suspension when cylinder pressures elevate in the transition to a low speed high load condition, encouraging LSPI of those suspended particles of lowered octane fuel/oil mixture). I don't understand where you misconstrued this to be anything related to normal engine knock.


Further, LSPI hasn't been solved with any engine, it's not even a fully understood phenomenon. If you find any document where Hyundai has claimed that it can't occur with this engine (or any manufacturer who has claimed that) post it so I can read it. I'm genuinely interested and can admit when I'm wrong so don't take that as a rhetorical challenge. Just because they've implemented some prevention strategies for it doesn't mean it's no longer a concern. Yes, it's a lot less of a concern than it was a decade ago, but I've seen no indication it's fully solved. Read some of the latest SAE papers on it. There's still a lot of unknowns and till they fully understand it there won't be any engine that's not still susceptible to it.



Also, the upgrade to the knock sensing software has nothing to do with LSPI. I have not seen any TSB mentioning that it does. The changes it makes to trigger limp mode and the P1326 code are to prevent a driver from causing a catastrophic failure after an engine has developed lower end bearing noise.

Until you quit plagiarizing off the internet and comment with some actual personal experience and some mechanical aptitude, you're going to keep getting tapped. I understand fully, know it when I read and see it as well.

There is no LSPI issue with the VN, period! There have been no failures of the 2.0T Theta II Veloster Engine attributed to LSPI. So what you're commenting is, false and misleading information and causes other inexperienced members undue grief and concern. It doesn't bode well for you personally and stands out like a sore thumb.

I've been at this a long time. Most likely, longer than you been alive. Most of us here, are mechanically inclined. Some of us, very savvy both mechanically and with internet as well. This also includes specific information with regards to the VN.

No one here including myself, requires your personal instruction or tutoring. Relax, stop trying so hard. This forum is meant to be enjoyable and informative, not a chore or issue.:smile: