Toyota’s 1.0 VVT-i engine is not one, but two technically different designs (1SZ-FE and 1KR-FE). The first has four cylinders. The second, three cylinders. Which 1.0 VVT-i engine is better?
Toyota 1KR series engines belong to the class of low-power compact 3-cylinder units. They are developed at a subsidiary of Toyota Corporation – Daihatsu Motor Co. The flagship of the series is the 1KR-FE engine, which was first introduced in November 2004 on the new Daihatsu Sirion for the European market.
The practical experience of operating the Sirion hatchback in Europe very quickly showed car specialists around the world that Daihatsu engineers managed to create a great engine specifically for small city cars.
The main advantages of this internal combustion engine are low weight, efficiency, good traction in a wide range of low and medium speeds, as well as a minimum level of harmful emissions.
Thanks to these qualities, in subsequent years, the 1KR engine thoroughly and widely settled not only under the hoods of small cars of Daihatsu and Toyota, but also began to be successfully used in compact cars from third-party manufacturers such as Citroen-Peugeot and Subaru.
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The design features of the Toyota 1KR-FE engine are as follows
- All major engine parts (cylinder head, BC and oil pan) are made of light aluminum alloy, which provides the unit with excellent weight and dimensions, as well as a low level of vibration and noise;
- Long-stroke connecting rods, coupled with the VVT-i system and the intake duct geometry optimization system, allow the engine to develop a fairly high torque over a wide rev range;
- Pistons and piston rings of the engine are coated with a special wear-resistant composition, which significantly reduces power losses due to friction;
- Compact combustion chambers provide optimal conditions for the ignition of the fuel mixture, which leads to a reduction in harmful emissions.
Specifications
| Parameter | Meaning |
|---|---|
| Manufacturing company / factory | Daihatsu Motor Corporation / Kurume plant |
| Model and type of internal combustion engine | 1KR-FE, petrol |
| Release years | 2004-present |
| Configuration and number of cylinders | Inline three-cylinder (R3) |
| Working volume, cm3 | 996 |
| Bore / Stroke, mm | 71.0 / 84.0 |
| Compression ratio | 10.5:1 |
| Number of valves per cylinder | 4 (2 inlet and 2 outlet) |
| Gas distribution mechanism | Single row chain, DOHC, VVTi system |
| Max. power, hp / rpm | 67 / 6000 (71 / 6000*) |
| Max. torque, N m / rpm | 91 / 4800 (94 / 3600*) |
| Fuel system | EFI – distributed electronic injection |
| Ignition system | Separate ignition coil per cylinder (DIS-3) |
| Lubrication system | Combined |
| Cooling system | Liquid |
| Recommended octane number of gasoline | Unleaded gasoline AI-95 |
| Approximate fuel consumption in the urban cycle, l per 100 km | 5-5.5 |
| Environmental regulations | EURO 4 / EURO 5 |
| Material for the manufacture of BC and cylinder head | Aluminium alloy |
| Weight of internal combustion engine with attachments (approximate), kg | 69 |
| Engine resource (approximate), thousand km | 200-250 |
* – specific parameter values depend on the settings of the engine control unit.
Applicability
Below is a complete list of cars from different manufacturers on which the 1KR-FE ICE has been installed and is being installed so far:
- Toyota Passo (05.2004-present);
- Toyota Aygo (02.2005- present);
- Toyota Vitz (01.2005-present);
- Toyota Yaris (08.2005-present);
- Toyota Belta (11.2005-06.2012);
- Toyota iQ (11.2008-present);
- Daihatsu Sirion;
- Daihatsu Boon;
- Daihatsu Cuore;
- Subaru Justy;
- Citroen C1;
- Peugeot 107.
Engine modifications
Especially for the Asian automotive markets, Toyota developed two simplified modifications of the 1KR-FE engine on the 1KR-FE engine platform: 1KR-DE and 1KR-DE2.
Production of the 1KR-DE ICE began in 2012 in Indonesia. This power unit was intended to equip the Toyota Aqva and Daihatsu Ayla urban compacts manufactured by the Astra Daihatsu joint venture and supplied to the local market as part of the Low Cost Green Car program.
The 1KR-DE engine is distinguished from its “parent” by the absence of the VVT-i system, as a result of which its characteristics have also become “modest”: maximum power is 48 kW (65 hp) at 6000 rpm, torque is 85 Nm at 3600 rpm.
The diameter and stroke of the pistons remained the same (71 mm by 84 mm), but the volume of the combustion chamber increased slightly – up to 998 cubic meters. cm.
Instead of aluminum, heat-resistant rubber-plastic was chosen as the material for the manufacture of the 1KR-DE cylinder head, which made it possible to reduce the total weight of the engine by almost 10 kg.
For the same purpose, an exhaust manifold and a catalytic converter with an oxygen sensor were integrated into a single construct with the cylinder head.
In 2014, in Malaysia, at a joint venture with Daihatsu, the production of the Perodua Axia hatchback began, on which they began to install a more powerful version of the 1KR-DE engine – 1KR-DE2. The increase in power was achieved by slightly increasing the compression ratio of the working mixture – up to 11:1.
The 1KR-DE2 produces a maximum of 49 kW (66 hp) at 6000 rpm and 90 Nm at 3600 rpm. Other characteristics are completely similar to those of the 1KR-DE engine. The engine meets the environmental requirements of EURO 4, and to achieve a higher standard, it clearly lacks the VVT-i system.
It should be noted that the 1KR-DE2 ICE produced in Malaysia is used on another Toyota model. This is a Toyota Wigo car, which is assembled by a subsidiary of a Japanese corporation and supplied to the Philippine automotive market.
The Chinese, based on the 1KR-FE engine, developed and created their own similar three-cylinder internal combustion engine with the BYD371QA index.
Service recommendations
The Toyota 1KR engine is a complex modern power unit, so its maintenance issues come to the fore. A prerequisite for maintaining the resource built into the engine by the manufacturer is the timely replacement of engine oil, filters and spark plugs. Use only high quality 0W30-5W30 SL/GF-3 engine oil.
Failure to comply with this requirement can lead to clogging of the valves of the VVT-i system and further failure of the engine as a whole.
Like most other ICEs made from light alloys, the 1KR-FE is a “disposable” engine, which means that if its internal parts and surfaces are damaged, it is almost impossible to repair them.
Therefore, any extraneous knock inside the engine should be a signal for the owner to establish the cause of its occurrence and promptly eliminate the identified defect. The weakest link in the internal combustion engine is the timing chain.
Contrary to popular belief that the circuit practically does not fail, the resource of this device is much less than the total resource of the internal combustion engine. Replacing the timing chain with a 1KR-FE after 150-200 thousand kilometers is quite common.
According to the reviews of the owners, the repair of the 1KR-FE engine most often involves the repair of attachments or electronic devices and systems that make up the engine.
Problems appear mainly in age-related products and they are associated, for the most part, with clogging of the VVT-i valves and throttle.
Additional fame for the 1KR-FE engine was brought by snowmobile owners who are happy to purchase contract engines of this model and install them in place of factory units. A striking representative of such tuning is the Taiga snowmobile with a 1KR engine.
Toyota 1SZ-FE 1.0 VVT-i Engine
In the late nineties, Toyota was getting ready for a very important premiere. The Japanese will present a B segment car. The hatchback body should bring a revolution. In order not to stop the successful sales of the vehicle, the engineers cannot bear technical losses in the case of driving.
Therefore, they decided to consult with the creators of Daihatsu and together they created a small petrol engine. Toyota’s 1.0 VVT-i engine dubbed the 1SZ-FE receives a cast iron block, 4 cylinders, 16 valves and 68 horsepower. And a little technical information doesn’t stop there.
1SZ-FE Specs
Oil pot 1.0 VVT-i holds 3.2 liters of oil. In addition, timing drive is carried out by a maintenance free chain, the variable valve timing system is standard, and valve lash adjustment is performed manually. The high working culture of the engine is undoubtedly good news for drivers.
1SZ-FE Performance
However, the performance is even better. 68 horsepower available is quite high – at 6,000 rpm. The same is true for torque – 90 Nm is achieved at 4,100 rpm. However, this did not prevent the Yaris, which weighs less than a tonne from reaching the top 100 in 13.6 seconds.
1SZ-FE Engine Problems & Reliability
The fuel requirements are even more reasonable. Toyota’s 1SZ-FE 1.0 VVT-i 4-cylinder engine consumes 6.9 liters of gasoline in the city. Outside the city, a quiet driver can reduce fuel requirements by up to 5 liters! Is it worth installing LPG in this engine? Experts don’t recommend it. According to them, the engine may not be able to hold the gas supply. In practice, this can be different. There are many cars in world that work quite well on low budget fuel.
In terms of failure rate, Toyota’s 1.0 VVT-i engine with the designation 1SZ-FE has basically no list of failure characteristics. It works without problems and remotely. Today, there are many examples that have covered nearly 400,000 kilometers so far. What mistakes did the driver complain about? The most common information is that lambda probes require lambda probes after a decade of operation. Other elements are perfect.
Toyota 1KR-FE 1.0 VVT-i Engine
2005 saw a notable change to the Toyota lineup. The manufacturer presents the second generation Yaris and a small B segment hatchback – the Aygo model. On this occasion, the 1.0 liter VVT-i 1SZ-FE engine was replaced with a more modern design.
1KR-FE Specs
During work, Japanese engineers removed one cylinder and made aluminum blocks and heads. They also use 12 valves and basically keep the 1KR-FE engine weight at the same level. Gasoline weighs 69 kilograms – only one kilogram heavier than its predecessor. What hasn’t changed? First of all, multi-point fuel injection, maintenance-free time chain and the fact that the engine is not recommended for LPG.
Small 1KR-FE 1.0 VVT-i petrol in 3 cylinder version produced in Japan. Engines are used primarily to power Toyota cars. I am talking specifically about the second and third generation Yaris.
1KR-FE Performance
Toyota’s 1.0 VVT-i engine called the 1KR-FE offers capabilities very similar to its predecessor. Strength reaches 69 horsepower and is developed at 6,000 rpm. Torque 93 Nm at 3,600 rpm.
How does this translate to acceleration? The second generation Yaris reached the first hundred in 15.7 seconds. The Aygo has a sprint time of up to 100 km / h which is set at 14.2 seconds. While driving, the biggest disadvantage of a small engine gasoline engine from Japan becomes clear – it becomes very noisy at high revs.
1KR-FE Installed
In addition, the 1KR-FE engine is used by the so-called Triplet Choline – the Toyota Aygo, Citroen C1 and Peugeot 107 and the Chinese Daihatsu, Subaru or even BYD models. In 2010, the 1KR-FE engine won an important award. He was awarded the title International Engine of the Year.
1KR-FE Engine Problems & Reliability
Toyota’s 1KR-FE 1.0 VVT-i engine was praised for its economy. The first generation Aygo consumed only 5.5 liters of gasoline in the city. And low appetite translates into another priority of the 21st century, which is ecology!
At the time of its market debut, the gasoline engine from Japan met the Euro 4 emission standard. Soon after that it was engineered to the Euro 5 standard, to meet the Euro 6 standard in 2014, grams of CO2 after each kilometer. This is a good result compared to the structure proposed by the competition.
The 1.0 VVT-i 1KR-FE engine didn’t have a reputation for being an overly malfunctioning engine. However, although in the case of the predecessor it is difficult to pinpoint even one problem due to technical error, not age, here the list consists of two items.
- First, the thrust clutch bearing is poor quality. Usually no more than 80,000 kilometers.
- Second, water pump leaks occur frequently.
Fortunately, these two characteristic problems do not mean that the engine should be eliminated. This 1KR-FE is one of the less problematic engines currently available in segments A and B.
1KR-DE, 1KR-DE2 Engine
Conclusion
The Japanese in the 21st century do not always ensure the reliability of their technology, and to find out, it is enough to remember the error in the cylinder liner of the 2.2 D-4D diesel.
Fortunately, the 1KR-FE and 1SZ-FE 1.0 VVT-i petrol exhibits the old Japanese school rules. As a result, regardless of whether the driver chooses the 4 or 3 cylinder version, there are a few things he should not worry about. This engine will be economical and very durable.
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