The Hyundai/Kia Nu engine is an all-aluminum inline-4 cylinder powerhouse that replaced the outgoing Beta engine series. It served as a stop-gap to bridge the need for a 1.8L/2.0L inline-4 between the 1.6L Gamma and 2.0L Theta II engines. While the Nu is often considered a solid engine, it does have a few significant issues including piston ring failure, piston slap, and fuel/oil dilution which can all do serious damage to the engine itself. Aftermarket support is very limited for the Nu, with only a handful of aftermarket modifications available for it.
In this guide, we’ll cover everything that you need to know about the Hyundai/Kia Nu inline-4 engine including its history, variants, design, common problems, and popular modifications. For more Hyundai content, take a look at our Hyundai 2.4 Oil Consumption Guide and our 4 Common Hyundai 1.6 Engine Problems Guide.
Hyundai Nu Engine History
The Nu was Hyundai’s inline-4 cylinder replacement for the outgoing Beta series of engines that was in production from 1995 to 2012. The newer Nu engine series was designed by Hyundai to be somewhat of a fill-gap between the 1.6L Gamma and 2.0L Theta II engine variants as well. As a result, it was offered in two different displacements, including a single 1.8L variant and 8 different 2.0L variants.
Most of the changes to the engine’s design arrived on the 2.0L variants of the Nu. The first major revision arrived on the G4ND variant of the 2.0L Nu, which added variable valve lift technology. A later Atkinson Cycle variant of the engine was also added to the lineup in 2015, improving fuel economy and thermal efficiency. Hyundai also released direct-injected variants of the 2.0L in 2012. As time went on and fuel and hybrid technology became more advanced, Hyundai released new variants of the 2.0L Nu accordingly. Those included a FlexFuel version in 2015, a hybrid variant in 2011, and a liquid petroleum version in the same year.
While the majority of vehicles that were powered by the Nu are not powered by the Smartstream G2.0 engine series, vehicles including the Kia Forte, Kia Seltos, and Kia Soul are still powered by the 2.0L Nu.
Hyundai Nu Engine Specs
| Engine | Hyundai/Kia Nu Engine |
| Configuration | Inline-4 Cylinder |
| Displacement | 1.8/2.0 Liters (109.7cuin/122.0cuin) |
| Aspiration | Naturally Aspirated |
| Valvetrain | DOHC 16V D-CVVT |
| Block/Head | Aluminum/Aluminum |
| Bore x Stroke | 81mm ×87.12mm/81 mm × 97 mm |
| Compression Ratio | 10.3:1–12.7:1 |
| Weight | Long Block ≈ 230-264lbs |
| Horsepower | 147–174hp |
| Torque (lb-ft) | 131–157lb⋅ft |
Hyundai 1.8/2.0 I4 Design Overview
The Hyundai/Kia Nu engine shares a very similar overall design to other engine series that were released at a similar time. Since the Nu was designed to fill the gap between the 1.6 Gamma and 2.0 Theta II engines, the Nu carries over many of the same attributes. With that being said, the Nu also built upon the Beta engine series that it replaced.
Like the Gamma and Theta II engine series, the Hyundai Nu’s block and cylinder head are made from aluminum. That is a departure from the Beta, which featured a cast iron block. The Nu’s use of aluminum doesn’t impact strength at all, but it does shave off around 30% of the weight of the Beta’s cast iron block. That’s equivalent to around 75 lbs.
In addition to the weight savings, the Nu is also packed with many of the new-age features that you’d expect from a modern inline-4 engine series. The Nu is equipped with continuously variable valve timing on both the intake and exhaust camshafts and hydraulic engine mounts for maximum power and efficiency. The Nu’s valvetrain also received somewhat of a makeover, with roller swing arms and hydraulic lash adjusters that reduce valve-driven friction to improve fuel economy by one percent compared with direct valve driving.
Most Common Hyundai 2.0T Nu Engine Problems
- Piston oil ring recall
- Piston/valve/connecting rod slap issues
- Fuel-diluting engine oil
While the Hyundai Nu is a reliable engine overall, it does have a couple of issues that can lead to serious damage to the engine itself. One of the Nu’s most prevalent issues revolves around the engine’s piston ring design. Hyundai’s manufacturing process is to blame, as the NHTSA concluded that the Nu’s piston rings weren’t adequately heat treated. Both the MPi (multi-port injection) and GDi (direct injection) variants of the Nu were affected by the problem. The faulty rings can cause under-hood fires and stalling, which can put the driver at risk. It also causes excessive oil consumption that can produce issues of its own. Hyundai/Kia has acknowledged the issue and will inspect and, if necessary, replace the engine at no cost to the owner.
The 2.0L Hyundai Nu engine is also notorious for having piston slap issues which can cause serious damage to the engine itself. In a 2014 technical service bulletin, Hyundai stated that the piston slap issue is caused by defects in the piston skirt coating, allowing the pistons to rotate and slap against the cylinder wall, causing extensive damage to the block. The problem is especially bad during startup, before the piston expands to fill the rest of the cylinder. Unfortunately, Hyundai requested that dealerships reject any warranty claims unless the owner could provide perfect oil change records.
In recent months, another potential issue has surfaced regarding fuel diluting the Nu’s engine oil. While no cause has been identified yet, it is becoming an increasingly common issue on GDi variants. You can read more about the issue here.
Best 2.0 Nu Engine Modifications
If I’m being totally honest, the Hyundai Nu is far from the best engine to modify. At this point in time, there isn’t a very big aftermarket community for the Hyundai Nu and there are very few parts manufacturers out there that produce performance parts for it. Additionally, with the serious issues that plague the Nu, adding significant amounts of power to the engine isn’t a very safe bet. With that being said, there are a couple of worthwhile bolt-on modifications that you can install on a Nu-powered Hyundai/Kia.
An aftermarket intake is a good addition to any Nu-powered vehicle and one of the only bolt-ons that is widely available for the engine. An intake can not only provide better breathability for your Nu, but also introduce some new fun noises into the equation as well. While the performance benefits of an upgraded intake might not be the most significant, it is a relatively inexpensive starter modification. There are aftermarket intakes available for everything from the Elantra to the Soul, so it should be easy to find one for your vehicle.
Outside of an intake upgrade, an exhaust is another good bolt-on for any Hyundai or Kia. Cat-back exhausts are the most common upgrade option for most Nu-powered vehicles. Cat-back exhausts replace all of the factory components from the catalytic converter to the exhaust tip. At the end of the day, cat-back exhausts are cosmetic and sound-improving modifications. Most factory Hyundai/Kia exhausts are very underwhelming from a sound perspective and an upgraded one can make the driving experience much more enjoyable.
Altogether, you can expect around a 10-15 horsepower gain from an intake and exhaust upgrade on most Nu-powered vehicles.
The Hyundai/Kia Nu is a Respectable Powerhouse with a Few Notable Issues
Hyundai/Kia have had a pretty difficult run as far as their engine designs are concerned. In fact, most of their engines are plagued with some kind of serious issue. The Theta engines have issues with excessive oil consumption, and the Nu is unfortunately prone to the same kind of failure in addition to some other rather serious problems. Between issues with the piston ring design, the design of the pistons themselves, and a new fuel dilution issue arising, the Nu doesn’t exactly have the best reputation as far as reliability and longevity are concerned. With that being said, there are many Hyundai/Kia owners out there who are more than content with their Nu-powered cars.
The design of the Nu itself is a pretty solid formula. The Nu is an evolution of the Beta engine series that was discontinued in 2012 and brought some new innovations to the table. Its all-aluminum construction, use of variable valve timing on the intake and exhaust cams, and upgrade to hydraulic lash adjusters make the Nu a truly modern inline-4 engine that Hyundai/Kia can continually improve on. With that said, the Nu has successfully powered a wide range of vehicles since its introduction in 2010 and still does to this day.
For anyone looking for a Hyundai/Kia that has good modification potential, the Nu isn’t the engine to be looking at. While there are a few aftermarket parts available for Nu-powered Hyundais/Kias, there isn’t much power to be gained. The best that you’re going to do is an aftermarket intake and exhaust, as there aren’t any widely available tuning options for the Nu.
For more Hyundai content, take a look at our Hyundai Genesis 3.8 V6 Engine Guide.
