Let me introduce you to this engine by pointing at Toyota’s own family of series, the NR engines. NR engine series employs aluminum engine blocks and DOHC cylinder heads. It does not matter if it is meant to go outside the US market.
The NR engines also use multi-point or direct fuel injection and have four valves per cylinder. Dual VVT-i is standard on the 1NR, 2NR, 3NR, 4NR, 5NR, 6NR, and 7NR engines, while VVT-iW is standard on the 8NR engine, allowing it to operate in both the Otto and modified-Atkinson cycles to improve thermal efficiency.
The Toyota 7NR-FE is almost an identical engine to the 2NR-VE. However, this 7NR engine is bound to go into the Chinese market. Again, it has a slight difference in displacement than the 1NR-FE since this engine is based on the 2NR-VE version of the same family.
However, the 2NR-FE engine has gone through five revisions over an eight-year development period, and the 7NR-FE adopted the VE version to its liking.
The 7NR-FE engine is a part of the NR family of engines, as the name implies. Toyota’s NR engine family comprises a variety of compact inline four-cylinder engines ranging in capacity from 1.2 to 1.5 liters.
What are Toyota 7NR-FE Engines?
The Toyota 7NR-FE engine is a fuel-efficient engine found in the third-generation Toyota Yaris, some on Toyota Vios. Its DOHC configuration with two valves per cylinder for variable timing or dual VVT-i features delivers between 107 HP and 140 lb-ft of torque depending on application demands.
The Toyota 7NR-FE engine is an analog version of the 2NR-VE engine that has been offered in the Chinese market since its introduction. It has the same construction and other attributes as the 2NR-VE engine.
The collective changes include the incorporation of the exhaust manifold inside the cylinder head, which was a revolutionary invention used to reduce pollution starting from the 2NR base version. A dual VVT-i equipped variation was later created and originally used in the Toyota Avanza and numerous 1.5L models in the Asian market as
Engine Specifications and Design:
- Production Run: 2014 – Present
- Cylinder Head Material: Aluminum
- Cylinder Block Material: Aluminum
- Configuration: Inline 4
- Bore: 72.5 mm
- Stroke: 90.6 mm
- Valvetrain: DOHC four valves per cylinder
- Displacement: 1.5 L (1329 cc)
- Compression Ratio: 11.5
- Weight: 190 lbs.
- Maximum HP: 107 HP at 6,000 RPM
- Maximum Torque: 140 lb-ft at 4,200 RPM
Engine Design:
The main objective of the 7NR-FE engine is to be delivered in Chinese markets as the same framework engine as the 2NR-VEs. They are built similarly and have little to no variances. As a consequence, we can say that this engine is an exact replica of the 2NR-VE, which is also available in other markets.
Toyota, according to them, supplied Chinese versions of these engines due to production and shipping constraints. Because the majority of these Asian versions are made in Asia, plants in Western nations do not have to spend enormous quantities of money to transfer to Asia.
Cylinder Block
The Toyota 7NR-FE is a four-cylinder inline engine designed with efficiency and compactness in mind. Furthermore, the major goal is improving engine performance while lowering pollutants and fuel consumption.
Again, taking everything into account, the cylinder block is intended for small engines with high compression ratios. With its high compression rating for a low displacement, the aluminum “open deck” operates as a single robust component with thin cast-iron liners, delivering strength and power that will endure until the engine is replaced.
The wall thickness between these cylinders is only 7 mm; you won’t have to rebore your engine if something goes wrong; you’ll be ready to go right away.
The crankshaft axis has been relocated by 8 mm relative to the cylinder axis lines, decreasing wear by lowering the lateral component of the piston’s force applied on the cylinder wall. The crankshaft is equipped with four balancing weights, shorter journals, and separate main bearing covers.
Cylinder Head
The camshafts are maintained separately from the cylinder head in housing, which simplifies cylinder head design and production. Hydraulic lash adjusters and roller rockers are part of the valvetrain system. In Asian marketplaces, old-style adjustable tappets are still in use.
Toyota maximizes its performance by utilizing cutting-edge tech. The intake channel was simplified, and the airflow was adjusted using computer modeling, resulting in smoother, less turbulent airflow.
Any surfaces were softened to reduce or eliminate any rough edges that may cause drag when the engine was running, and all sharp curves were transformed into gently sloping ones.
2NR-VE Restructured
The Toyota 7NR-FE engine, like the 2NR-VE engine, is an intelligent, inventive, and efficient design with a new piston structure to reduce friction. Toyota, throughout the development of this engine, reduced the contact surface, allowing for improved gas sealing, which minimizes pumping losses and NOx emissions when compared to the previous model year’s version of this unit – all while sacrificing little weight or space.
Another feature of this engine is the cool exhaust recirculation. You can definitely feel good about driving your car on electricity rather than filthy gasoline injectors every day; it not only saves money but also improves our air quality.
To lessen the strain on your engine, pistons are anodized and coated with a PVD anti-wear compound. This makes it more efficient for you, which means you’ll get a greater gas economy with these pistons.
During the manufacturing process, piston coatings are generously coated to not only guard against corrosion but also to lengthen the life of the piston by minimizing systematic wear produced mostly by compression rings rubbing against each other or ring gear teeth scuffing off a piece of metal.
Application of Toyota 7NR-FE engine:
- Toyota Yaris NCP150 R China Market Only
- Toyota Vios China Market Only
Problems Surrounding Toyota 7NR-FE Engines
These are just a few instances of what may go wrong with a four-cylinder engine. There aren’t necessarily more difficulties than normal, but they’re nevertheless worth addressing because many individuals aren’t aware of these possible risks yet or assume their car is in good working order.
Because of its durability and economy, the Toyota 7NR-FE engine has become a different engine on its own. However, like any other equipment, it has weaknesses that must be addressed and identified in order to avoid problems later on. Let’s have a look at some of the more prevalent concerns of the Chinese analog of the 2NR-VE.
Some of the issues here can be seen at other NR engines since they share most of the issues. Among them are the following:
1. Excessive Soot Deposits
There are instances, and it is also declared as a problem with some engines. It has been discovered that some Toyota 7NR-FE and other NR engines take longer than the normal time required for ignition but also due to residue buildup within specific components such as pistons.
Excess soot deposits in the combustion chamber, valves, and valve seats can cause compression to be reduced, as this was the case across all NR engines, as we mentioned earlier. This causes the engine to take longer to start, resulting in the display of DTC P1604.
The problem is recognized by TSB EG-00037T-TME as an excessive deposit of this type, which may cause a reduction or loss of power.
2. Excessive Oil Consumption
The most well-known and common problem with NR engines, not only in the 1NR-FE, is high oil consumption, which generally presents itself at less than 60,000 miles. According to Toyota’s usual explanation, the piston rings are trapped.
Although cylinder block reboring is not required, the need to replace pistons and connecting rods at the same time prevents a low-cost engine renewal.
In TSB EG-0095T-1112, oil usage was noted as a source of concern. Early in 2017, production changes were implemented, such as revised rings and pistons with connecting rods, as well as valve cover replacement for those with greasy valves or nozzles.
3. Clattering noise from the Timing Chain area
Another issue that you might need to magnify is the foreign noise in the timing chain are. Well, you may have heard the grinding or clanking sound of your timing chain, which can be an indicator that it needs to be replaced. This is detailed in TSB EG-00039T – Toyota’s technical service bulletin for this issue.
There are two options available; either do nothing or just replace one part by installing a new tensioner arm on top of their already installed engine block without changing any other parts.
4. Rattling or Knocking Noise During Operation
During engine operation, large deposits in the combustion chamber cause a rattling or banging noise. This problem is acknowledged and explained in TSB EG-0094T-0714, which describes some production adjustments introduced at the beginning of 2014 to fix it for good.
The engine’s performance can be dramatically improved with this part’s new, more customized variant. You’ll also want to get your hands on ECU firmware that has been reprogrammed for increased gas mileage and power output.
Summary
The Toyota 7NR-FE engine is a great choice for those looking to have some fun on their way through town. As it is made for such purposes. Generally, Chinese bound or any Asian bound vehicles are focused on city driving.
The engine capacity is just right at the sweet spot between not so small and not so large it gulps down gasoline in no time. With the Toyota 7NR-FE, the engine is a great choice for those who want a fuel-efficient engine.
Add its aftermarket support, easy access to the spare parts, and its great fuel economy; you’ll never regret owning this dependable little road machine. When all of these characteristics are combined into one little package, the new generation Toyota NR is unbeatable.
I really want to emphasize its fuel economy; this inexpensive and dependable engine will take you everywhere. It has no major flaws, making it an excellent alternative for anybody looking to save money on vehicle payments or just be able to travel around town effectively.