What's Killing Your Toyota G16E GTS Engine? GR Yaris & GR Corolla

Summary

The video script discusses the issues with the G16E-GTS engine in Toyota GR Yaris and GR Corolla, which often leads to engine failures. It explains the problem of incorrect piston ring tolerancing causing 'mega blow-by' and potential engine fires. The narrator advises using the correct oil viscosity and changing it frequently, and suggests engine forging as a preventive measure. The script also mentions Toyota's warranty claims and the potential for new technologies to address the issue.

Takeaways

• 🔧 The Toyota GR Yaris and GR Corolla have had issues with their G16E-GTS engines blowing up under various conditions.
• 🏎️ The three-cylinder engine design allows for better scavenging and higher power output at higher revs while maintaining stability at low RPM.
• ⚙️ The issue stems from incorrect tolerancing in the piston rings of the Gen.1 GR Yaris engines, leading to excessive spacing.
• 💥 The excessive piston ring spacing can cause oil to be forced into the combustion chamber, leading to mega detonation and engine failure.
• 🔍 The engine failure is not due to normal knocking or component failure but is a specific issue with the piston ring design.
• 🔥 Mega detonation can cause severe engine damage, including piston destruction and conrod ejection, which can lead to engine fires.
• ⚠️ The problem affects both stock and tuned engines, and there is no specific repeatable condition that causes the failure.
• 👨‍🔧 To prevent engine failure, it's recommended to have the engine forged with new, correctly toleranced pistons and conrods.
• 🏁 It's crucial to use the correct oil viscosity (5W30 API SP) and to change the oil frequently to prevent blow-by.
• 📈 There are ongoing developments, such as HKS's new long-block engine and combustion technology, to address the issue.

Q & A

What is the main issue with the G16E-GTS engine in the Toyota GR Yaris?

The main issue is the incorrect tolerancing of the piston rings, leading to excessive spacing and causing mega blow-by, which can result in engine damage or failure.

Why did Toyota choose a three-cylinder engine for the GR Yaris?

Toyota chose a three-cylinder engine for better scavenging and the ability to make more power higher up in the revs while retaining stability at low end.

What is meant by 'mega blow-by' in the context of the GR Yaris engine?

'Mega blow-by' refers to excessive amounts of oil and combustion gases bypassing the piston rings and entering the crankcase, leading to abnormal pressure and potential engine damage.

How does the piston ring issue lead to engine fires in the GR Yaris?

The piston ring issue can cause mega detonation, which destroys the piston and rod, potentially pushing the rod through the engine block and causing oil to leak out and ignite, leading to fires.

What is the recommended oil viscosity for the GR Yaris engine?

The recommended oil viscosity for the GR Yaris engine is 5W30 API SP.

What is the significance of the piston crown being very black on the GR Yaris engine?

The blackening of the piston crown is due to carbon build-up from the piston rings, indicating excessive blow-by and potential ring issues.

What is the suggested preventative measure for engine failure in the GR Yaris?

The suggested preventative measure is to have the engine forged with new, correctly toleranced pistons and rings.

What is the role of the oil squirters in the engine failure of the GR Yaris?

The oil squirters can contribute to the issue by spraying oil upwards, which can pass through the incorrectly spaced piston rings and cause combustion issues.

What is the condition that puts the most strain on the GR Yaris engine?

The condition that puts the most strain on the engine is spooling the turbo in fifth or sixth gear from low RPM outside of the compressor map’s optimal points.

What is the current solution offered by aftermarket companies like HKS for the GR Yaris engine issue?

HKS is developing a new long engine with improved combustion technology, similar to strategies used by Ferrari, to address the engine issues.

What is the advice for drivers of the GR Yaris to prevent engine issues?

Drivers should ensure proper heating and cooling of the engine, use the correct oil viscosity, and consider engine modifications such as forging for added safety.

Outlines

00:00

🔍 Investigating the Toyota GR Yaris Engine Failures

The script discusses the concerns over the G16E-GTS engine found in the Toyota GR Yaris and GR Corolla, which have been reported to fail both in stock and tuned conditions. The presenter is exploring the reasons behind these failures, noting the engine's three-cylinder design allows for better scavenging and higher power at higher RPMs while maintaining stability at lower RPMs. The issue seems to stem from incorrect tolerancing in the piston rings, leading to excessive spacing, which causes cavitation and ultimately results in mega detonation. This phenomenon damages the engine severely, and the presenter suggests that the only safe option for Gen.1 GR Yaris owners might be luck, as the engine can fail under high pressure and incorrect oil ring gaps.

05:02

🔧 The Piston Ring Issue in GR Yaris Engines

This section delves deeper into the technical aspects of the engine failure, focusing on the piston rings' incorrect gap measurements. The presenter explains that the gap is alarmingly large, which is a critical issue because it allows oil to bypass the rings and enter the combustion chamber, leading to mega detonation. The use of thinner oil under pressure exacerbates the problem. The presenter also advises on engine operation to prevent such failures, such as avoiding extreme conditions like spooling the turbo at high gears and ensuring the engine is properly warmed up and cooled down. Additionally, the presenter mentions warranty claims and incidents of engine fires due to the detonation, which can push the conrod through the block, causing oil to leak and potentially ignite.

10:06

🛠 Solutions to Prevent GR Yaris Engine Failures

The final paragraph offers potential solutions to the engine failure issue. The presenter suggests that the only way to prevent such failures is to have the engine forged, which involves replacing the pistons and conrods with forged ones that have correctly toleranced piston rings. This process has proven successful, with no failures reported in over 30 engines. The presenter also mentions HKS's development of a new long-block engine with improved combustion technology. As a temporary measure, the presenter advises using the correct oil viscosity (5W30 API SP) and ensuring frequent oil changes to prevent oil from bypassing the piston rings. The presenter emphasizes the importance of being mechanically conscious and allowing the car to cool down properly after use.

Keywords

💡G16E-GTS engine

The G16E-GTS engine is a three-cylinder engine used in the Toyota GR Yaris and GR Corolla. It is the main focus of the video, as the script discusses its issues and failures. The engine is noted for its high performance capabilities but also its tendency to 'blow up' under certain conditions, which is a central theme of the video.

💡Blow up

In the context of the video, 'blow up' refers to the engine failing catastrophically, often due to excessive pressure or heat. The script mentions that these engines are known to 'blow up' on the motorways, both in stock form and when tuned, indicating a significant issue with reliability.

💡Scavenging

Scavenging in an engine refers to the process of removing exhaust gases from the combustion chamber. The video explains that the three-cylinder design of the G16E-GTS engine provides better scavenging compared to inline four or six-cylinder engines, which allows for more power at higher RPMs while maintaining stability at lower RPMs.

💡Variable cam timing

Variable cam timing is a technology that adjusts the timing of a vehicle's camshaft to optimize performance. The script mentions this technology as a factor that allows the engine to retain stability at low RPMs while still making power at higher RPMs.

💡Mega Blow-By

Mega Blow-By is a severe condition where excessive amounts of combustion gases bypass the piston rings and enter the crankcase. The video script describes it as a major issue with the G16E-GTS engine, leading to high pressure in the crankcase and potential engine damage.

💡Piston rings

Piston rings are part of the piston assembly that create a seal between the piston and the cylinder wall. The script identifies incorrect tolerancing in the piston rings of the G16E-GTS engine as a cause of the Mega Blow-By issue, leading to engine failure.

💡Cavitation

Cavitation refers to the formation of vapor bubbles in a liquid due to low pressure. In the context of the video, cavitation occurs within the cylinder bore of the engine, which can lead to damage. The script mentions micro cavitation as a contributing factor to the engine's issues.

💡Oil squirters

Oil squirters are devices that spray oil onto the underside of the piston to help cool it and reduce friction. The video script explains that the G16E-GTS engine has three oil squirters, which can contribute to oil particles getting into the combustion chamber and causing detonation.

💡Detonation

Detonation in an engine refers to a type of abnormal combustion that can cause severe damage. The script describes 'mega detonation' as a result of oil particles mixing with fuel and igniting at the wrong time, leading to engine destruction.

💡Forged pistons

Forged pistons are made from a solid piece of metal and are stronger than cast pistons. The video suggests that using forged pistons with correctly toleranced rings can prevent the engine failures experienced with the G16E-GTS engine.

💡API SP oil

API SP oil is a high-quality motor oil that meets the latest industry standards. The script emphasizes the importance of using 5W30 API SP oil in the G16E-GTS engine to prevent oil from bypassing the piston rings and causing blow-by.

Highlights

Introduction to the problem of G16E-GTS engine failures in Toyota GR Yaris and GR Corolla.

Explanation of the engine's three-cylinder design and its impact on performance and stability.

Misalignment of piston rings leading to excessive spacing and potential engine failure.

Detailed description of the 'mega blow-by' phenomenon causing engine damage.

Observation that engine failures occur both in stock and tuned conditions.

Analysis of the piston crown and ring gaps indicating improper gapping.

Discussion on the importance of using the correct oil viscosity and quality to prevent blow-by.

Advice on proper engine heating and cooling to prevent failures.

Mention of documented cases of engine failures and Toyota's warranty claims.

Explanation of how engine fires can occur due to oil leakage and high temperatures.

Emphasis on the rarity of the issue affecting only a small number of Gen.1 vehicles.

Recommendation to have the engine forged to prevent future failures.

Success of forged engines in preventing failures, even under high performance conditions.

Mention of HKS's new long engine and combustion technology as a potential solution.

Advice to consult a good mechanic for engine preparation and maintenance.

Importance of acknowledging the problem and taking preventive measures.

The presenter's personal experience and mechanical consciousness in avoiding engine failure.

Conclusion and anticipation for future developments and updates on the issue.

Transcripts

Hi guys!

So I have thought long and hard IF to do this video

and in which way to do this video, but in the end, here we are :-)

This is a full, broken G16E-GTS engine from a Toyota GR Yaris.

And obviously it's basically the same thing with the GR Corolla.

So what is happening with these engines and why are we reading

always more that these cars are like... Blowing up on the motorways?

They're having issues and they're blowing up as stock...

They're blowing up when they're tuned.

But still there is no, let's say, major factor collecting any of these.

So this is very strange.

And I'm here to talk to you of the reason.

So first and first, obviously this is a three cylinder engine.

And this means that the timing of each cylinder is a bit longer

and there is a very, long time

with no overlap for each cylinder.

This means that it's got a better scavenging that, let's say four

cylinder or six cylinder engines if they're inline engines.

And this is why, Toyota initially decided to take this engine into account.

This means you can make more power and make it higher up in the revs

and, still retaining, quite the stable engine at the low end.

Thanks to nowadays all the variable cam timing and all of that.

So why is it that these engines are breaking, on us?

It's like we're back in the era of Subarus where everybody was scared

of their engines blowing up and everybody was forging their engines.

But is there a way to be safe with the stock engine?

And I'm talking especially of Gen.1 GR Yaris, or is there not?

Well, spoiler alert there is not.

You have to be very lucky.

So what happens is an episode of,

MEGA BLOW-BY : basically,

to make a long, long story a bit shorter, what happens is

these pistons that you find in the Gen.1 GR Yaris,

but also the modified ones you find in the GR Corolla,

have a tolerancing

that is not correct in the piston, rings.

So these piston rings, I've got too much of a spacing in them.

And due to the longer

stroke of in the bore and the longer timing,

the pistons have some moments of cavitation,

micro cavitation, of course, within,

within, the cylinder bore.

So what happens is with the,

the ample tolerances that are given by the piston rings,

what happens is that basically

you get in the great pressure when the piston goes down

and makes a huge pressure in the crankcase.

And you've got three not one but three oil squirters,

squirting oil upwards happens.

Is that some particles of oil

randomly manage to get through the piston rings.

These particles of oil then

go into the direct ignition chamber.

They mix with the fuel and they ignite at the wrong time.

Hence a mega detonation.

Okay, so I appreciate that it isn't so simple to understand.

and not so straightforward if you're not an engine builder.

So let's take a moment to observe a couple of pictures of G16E-GTS pistons.

The other two pistons that came out of the same engine.

So first things first.

The two Pistons had, actually no damage,

other than the one that actually exploded in its cylinder.

And also the whole bottom end of the engine had no, no damage whatsoever

apart from what happened in, obviously the cylinder that totally destroyed itself.

So this is telling us that we are not in front of,

a normal knock situation, and we are not in front of, a situation where, for example,

we were making too much power and the components, the piston itself

or its conrod were giving in.

But what I can show you now is that, basically the

piston crown that is the first part

above the piston is, as usual, very black.

And this is due to the fact that it's before it's based on rings.

But you see, it's also very dirty between the first and the second piston ring

and all the way down to the oil scraper.

What do I want to show you with this?

If you look now at the second picture,

You can see that the piston rings are held in the hand now,

and obviously they're not compressed all the way,

but we have measured the ring gaps and they are

absolutely something like two fold the distance they should be.

I will not enter into specific numbers, but the gap is

what is very, very alarming at the moment.

So what material was actually used and what quality of material.

Because the correct piston gapping is made in order

to admit some movement of the material itself

as the piston ring heats up by scraping against the the cylinder wall

to be able to expand.

But you have to gap it right...

Otherwise you're going to be either losing compression

or letting oil or something else get by together with the pressure.

So this is the main weak spot.

It's how the piston is made on its contact wall

and the piston ring gaps.

This is what breaks your engine.

Of course, the more pressure and the thinner oil

you use, the worse it gets.

And also certain conditions of use of the engine.

For example, spooling the turbo in fifth or sixth

gear from, let's say very low

rpm outside of the compressor map’s optimal points

is going to put more strain on the engine

and especially on the small turbo

that, when ECU mapped, does hit quite hard.

So beware of keeping your engine always with 5W30

API SP oil and of driving it in its optimal range.

And obviously when the car has to heat up or cool down,

please stop driving it at the maximum and not allow for some cooling down

and allow it to heat up in the mornings.

So let's get back to the future. Video.

I cannot say who I

worked on this project, and all the details around it,

but I as usual, I can tell you, I'm talking with accurate data here.

I can also show you some posts that are put on

by Japanese partners of Toyota, all the same

more than a year ago, and then removed because now Toyota is having warranty claims.

The last one in USA.

The guy that had the engine catching fire.

And we'll get to how this happens in just a moment.

And the Toyota was refusing to refund this engine and the damage to his car

because they were saying that he was he was speeding at, what,

85mph on the motorway with the GR Corolla?

I should be able to go to the track with my GR car and brake it,

and then have Toyota still help me out with it because they're selling these cars to be tracked.

It's not like we have all this performance for what?

So why do these engines, catch fire?

So it's clear that they suffer.

First of all, they suffer the mega blow by in any condition.

So we've got the case now of more than ten cars.

We've got documented cases.

And the fact is that these engines blow up

as stock and as tuned in any condition.

I mean, we've seen these engines fail

when they're idle after going fast,

but also and majorly in the most delicate moment for the piston,

that is when you're going flat out in a high gear,

say fifth or sixth gear for a long time, and then you,

you take your foot off the gas completely and quickly.

This is, for example, if you are on a long track, when you get down

the main straight and then you lift off for the main braking,

if you put this together, also with the oil scavenging issues, it's it's not so good.

But anyways, what happens is mega detonation occurs.

You can do nothing about it.

And when it occurs it destroys completely your engine

because obviously it destroys your head because the piston just detonates to pieces.

And obviously your conrod will come out of the block.

So this is why the fires happen.

You see this huge hole here in the block? Yes.

This is where the conrod was pushed out and it made a hole.

So can you can imagine at very high temperature,

over 100°C, oil

coming out of the block, because these squirters are still squirting oil everywhere,

and whatever it touches (...turbo, exhaust...) at that heat will just catch fire.

So it's not like the engine or the car goes on fire for some magic way.

It can catch fire if you are unlucky

in this specific episode

of Mega Blow by and

you are unlucky in the way that your conrod is pushed

out of the block, there is something that we're seeing a lot... Now:

I don't want to be, but terror with you

and be a terrorist about the engines of the gears.

Firstly, generation one is what we're talking about here,

and it's only a very small amount of cars on the total numbers.

Okay, my car is a Gen one.

I'm running stock pistons still, and I had no issues whatsoever.

But there is not a specific condition

that we can say is repeatable where this happens.

It's just that simple.

So what can you do to prevent this?

Basically, it's simple and expensive.

Unfortunately, you need to take the engine off the car and you need to forge it.

So when you have some new,

conrod and you have some new some that is drifting, just,

near here and sorry for that.

And you have some new, new pistons that are forged

with the correct tolerances in the piston rings.

Then we have not seen one engine fail yet

out of more than 30 engines at this point, not one at all.

And, there is one engine that already did something like 70,000km.

Not a problem with all the over 450 horsepower.

So we all know, for example, HKS is coming out not only with a new long engine,

but with new technologies of combustion in this, because obviously here,

it starts to get complicated, but they are trying to use and implement

the same strategy that,

Ferrari has done in their, pre induction chamber.

But I still have to see how this plays out.

Otherwise you can just go to a very good mechanic

of your knowledge and ask them to change your pistons and controls.

And this is the safest thing you can do for yourself in this car.

I am still, for my own car.

We we just did the preparation with the cams.

Very mild.

And, I'm still understanding what to do.

If I will then grab one of these HKS motors

in order to showcase them to you guys or what I'm going to do.

But in this case, it's very important that you acknowledge that there is a problem.

So to me, it did not happen because I am lucky, probably

also because I am mechanically conscious because, you know,

when you take a car of this, of this power, you always have to heat it up properly

and you also have to cool it down, especially when you come out of a motorway

or a track and you've been pushing, you got to leave the car.

Time to cool down before stopping the car itself, right?

Oils, I cannot stress this enough.

5W30 API SP is the right,

oil viscosity on this engine and high quality oils

frequent changes because this will not prevent the blow by.

But for sure, if the oil is not too diluted, it will prevent oil going by.

Because also this is another factor.

So I hope this was, a bit of, interest.

And I'll put up some detailed images now so you can see

and we're going to be very soon back in touch with the next developments.

See you man.