LSPI issue on all direct injection + turbo engines

LSPI short for low speed pre-ignition is an current issue for the next generation engine like the new 1.5t on the new honda civic's....

it means when the car is driving at low speed, the engine knocks...

most car manufacturer are still working on a fix on this issue (it's very serious) but one thing they found out is that engine oil is part of the problem.

oil with high calcium level will most likely contribute to this phenomenon, this is verified by ford, toyota, chevron & SAE..

if you google LSPI calcium oil, you will find a lot of actual studies & article about this issue...

so, when you choose an engine oil, make sure they are API certified and try to find their VOA (virgin oil analyst) & UOA (used oil analyst) and make sure the calcium level is low.

A Study on the Effect of a Calcium-Based Engine Oil Additive on Abnormal SI Engine Combustion

link: http://papers.sae.org/2014-32-0092/

the sae papar is $26 if you really wanna buy it...

Supercharged direct-injection engines are known to have a tendency toward abnormal combustion such as spontaneous low-speed pre-ignition and strong knock because they operate under low-speed, high-load conditions conducive to the occurrence of irregular combustion. It has been hypothesized that one cause of such abnormal combustion is the intrusion of engine oil droplets into the combustion chamber where they become a source of ignition. It has also been reported that varying the composition of engine oil additives can change susceptibility to abnormal combustion. However, the mechanisms involved are not well understood, and it is not clear how the individual components of engine oil additives affect autoignition.In this study, abnormal combustion experiments were conducted to investigate the effect on autoignition of a calcium-based additive that is typically mixed into engine oil to act as a detergent. The experiments were performed with a single-cylinder 4-cycle gasoline engine using a primary reference fuel (PRF 50) into which the calcium salicylate (CaSa)-based detergent was mixed at various ratios.The experimental results showed that autoignition occurred increasingly earlier with a higher concentration of the CaSa-based engine oil additive, giving rise to severe abnormal combustion. This indicates that the addition of a CaSa-based detergent to engine oil tends to promote autoignition and abnormal combustion.

Engine Oil Development for Preventing Pre-Ignition in Turbocharged Gasoline Engine

link: http://papers.sae.org/2014-01-2785/

Gasoline engine downsizing combined with a turbocharger is one of the more effective approaches to improve fuel efficiency without sacrificing power performance. The benefit comes from lower pumping loss, lower mechanical friction due to ‘downsizing’ of the engine displacement and ‘down-speeding’ of the engine by using higher transmission gear ratios which is allowed by the higher engine torque at lower engine speeds. However abnormal combustion referred to as Low-Speed Pre-ignition (LSPI) is known to be able to occur in low-speed and high-torque conditions. It is a potential restriction to maximize the engine performance and its benefit, therefore prevention of LSPI is strongly desired for long-term durability of engine performance.According to recent technical reports, auto-ignition of an engine oil droplet in a combustion chamber is believed to be one of major contributing factors of LSPI and its formulations have a significant effect on LSPI frequency. Toyota has reported that the oxidation stability of engine oil can be a dominant factor of its auto-ignition, which is a function of its base oil and additive components, of which an example was found that calcium-based detergents significantly increase LSPI frequency.Based on these findings, we have developed a new engine oil product which can reduce LSPI frequency to less than 10% of that of conventional ILSAC certified gasoline engine oils. High quality base oils (Group III, Group IV) and optimized additive components were formulated in which the amount of calcium-based detergent was reduced to levels lower than general ILSAC oils, and a sufficient amount of anti-oxidants were added. This newly developed engine oil is scheduled to be introduced for Toyota's new turbocharged gasoline engine vehicles. The new engine was released in July 2014 in the Japanese market. Toyota plans to subsequently launch the engine in Europe and the rest of the world.

SUMMARY/CONCLUSION (NOV/2014)

• Since LSPI is a serious issue for improving performance of turbo-charged downsized gasoline engines, many researchers have been engaged in verifying the mechanism of LSPI phenomena and proposing solution for suppressing LSPI. One of the most likely hypotheses is that auto-ignition of engine oil droplet released from piston crevices become a source of LSPI.

• This study focused on the effects of engine oil additives on LSPI frequency. Toyota clarified in the past SAE paper that Ca-based detergent works as LSPI-promoter, whereas ZnDTP and Mo-based anti-oxidant work as LSPIinhibitors.

• Utilizing statistical analysis, it was clarified that reducing the amount of Ca-detergent is the most effective approach and increasing the amount of ZnDTP and Mo-based antioxidant are also effective for LSPI reduction.

• Based on these results, a formulation capable to reduce LSPI frequency while maintaining the other basic performance was identified. The newly developed oil achieved the target of reducing the LSPI frequency to 10% of that of a conventional oil (API SM, 0W-20).

• Furthermore durability of LSPI prevention performance was evaluated through oil degradation test over 200 hours. The developed oil maintained an excellent performance of LSPI prevention till TBN became zero

And what do you propose we do about this situation?

SilverGhost said:

And what do you propose we do about this situation?

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Silver,
I propose that we drive the shit out of our Honda's like we always do! LOL JK!!!

Truckin said:

Silver,
I propose that we drive the shit out of our Honda's like we always do! LOL JK!!!

Click to expand...

Hells Yea brother,drive like I stole it.

Direct injection engines suffer from other valve deposits outside of this specific issue, from what I recall Honda positioned their injectors in the cylinder to help with valve deposits, in conjunction with the newly shaped pistons.

Oil catch cans won't prevent the deposit issue, it will just take longer for the deposits to accumulate, so they will occur at a slower rate.

I wish I could run my favourite oil - Red Line - high in Zn and MO, too bad it isn't API certified, maybe once my warranty is up I will start running it. I might run a maintenance dose of Red Line Fuel Injector treatment, to see if that helps.

JS2000 said:

Direct injection engines suffer from other valve deposits outside of this specific issue, from what I recall Honda positioned their injectors in the cylinder to help with valve deposits, in conjunction with the newly shaped pistons.

Oil catch cans won't prevent the deposit issue, it will just take longer for the deposits to accumulate, so they will occur at a slower rate.

I wish I could run my favourite oil - Red Line - high in Zn and MO, too bad it isn't API certified, maybe once my warranty is up I will start running it. I might run a maintenance dose of Red Line Fuel Injector treatment, to see if that helps.

Click to expand...

Will catch cans really not work?

looks like real short OCI's would be prudent til this all sorts out.

I'm sure Honda designed these new DI engines anticipating the carbon deposit issue,this issue has always bothered me but I guess I trust Honda engineers know what they are doing.And they want to mirror there past reputation of long running reliable engines.My .02 Lincolns

TranceFC1 said:

Will catch cans really not work?

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They work as intended , but they don't catch 100% of the oil vapours. So deposits will accumulate at a slower rate, but will eventually occur on the valves if it is an issue with this engine design. I trust Honda did better than Ford with their design. Many other manufacturers end up with cold start misfire issues if you look that up on the internet. Hopefully Honda has had more time to look at this and other issues with their designs.

Here is one of our favorite articles on LSPI: http://stratifiedauto.com/blog/low-...the-mazdaspeed-disi-and-ford-ecoboost-motors/

Basically you want to avoid high-load, low-RPM situations. So no flooring it in fifth or sixth gear if you have a manual. Small turbos that make a lot of boost low in the rev range can be very tough on rods and piston rings. Its best not to go full boost till around 2500-3000 RPMs. Also, always let your oil warm up before driving aggressively and getting into boost. Cold oil is rough on boosted cars.

JS2000 said:

They work as intended , but they don't catch 100% of the oil vapours. So deposits will accumulate at a slower rate, but will eventually occur on the valves if it is an issue with this engine design. I trust Honda did better than Ford with their design. Many other manufacturers end up with cold start misfire issues if you look that up on the internet. Hopefully Honda has had more time to look at this and other issues with their designs.

Click to expand...

I've found that atomizing a detergent through the TB works very well to limit deposits on the IM/runners/valves on turbo direct injection powertrains.

I have to believe Honda did their homework. And Hondata speculates they do a little magic during scavenging to help limits deposits on the intake valves. Time will tell...

If this was really an issue, wouldn't the computer be programmed to limit boost until warmed up, and wouldn't Honda have warnings. Doesn't look like it's an issue