Mitsubishi Engines: Common Problems and Key Specs

Mitsubishi is one of the most famous Japanese car manufacturers. Although now the company is going through one of the hardest periods in its life, it's still the power to consider when it comes to competition in the car market.

In this article, I will tell you promptly about several important engines used in modern and classic Mitsubishi vehicles. I will focus on key features while also giving you links to more detailed articles to read about certain engines.

This page is dynamic and it will be updated once I review another Mitsubishi engine.

Mitsubishi 1.5L 4B40 engine

This is the only representative of the 4B4 engine family launched in 2017. The 4B40 engine is the hope for the company to stay on the market. It's small and economical but still quite powerful.

For now, the 1.5L 4B40 engine only powers the Mitsubishi Eclipse Cross but the company may decide to use it in other vehicles, too. The engine is pretty simple in its engineering. There are even no hydraulic lifters. The camshafts are driven by the chain, there are MIVEC phasers on each cam.

To achieve optimal power, Mitsubishi installed the turbocharger in this 4-cylinder engine with limited displacement. Also, engineers solved the problem with buildup on intake valves by adding the row of port injectors.

Key features and my opinion:

• Production years:2017-now
• Average lifespan of 4B40:160,000-190,000 miles
• Fuel supply type:combined injection (direct+port)
• Power range:150-163 hp
• Fuel efficiency:good
• Engine block material:aluminum
• Engine reliability score:medium
• The most common problems:uneven RPMs when idling, complicated and expensive injection system, timing chain stretching.

Mitsubishi 1.2L 3A92 engine

The number 3 in the codename of this engine hints that there are 3 cylinders in it. Only 1.2 liters of displacement and limited power make this engine very narrow in its possible use. Actually, it's only used in the current generation of the Mirage and the Attrage sedan model.

The engine is pretty simple in its construction. There is no turbocharger, and there are also no lifters. The cams are driven by the chain and there is the MIVEC phaser system on each camshaft. That's all you should know about the engineering.

Thanks to small displacement, phasers, and limited power, Mitsubishi achieved wonderful fuel efficiency in this engine. It can be compared with hybrid specs on some other vehicles on the market.

But unfortunately, these engines are not really good in terms of overall reliability and durability.

Key features and my opinion:

• Production years:2012-now
• Average lifespan of 3A92:140,000-170,000 miles
• Fuel supply type:port injection
• Power range:78-80 hp
• Fuel efficiency:excellent
• Engine block material:aluminum
• Engine reliability score:medium
• The most common problems:bad oil consumption, weak timing chain and phasers, electronic throttle issues, thermostat problems.

Mitsubishi 2.0L 4B11 engine

The 2-liter 4B11 engine is great in terms of efficiency and simplicity in its design. It's one of the greatest engines Mitsubishi has ever made and that's why it has been in production for almost two decades now.

The 4-cylinder 2.0L gasoline engine has no turbocharger and still produces enough power for the ASX, Eclipse Cross, Outlander, Delica, and Lancer. Also, this engine was used in several Peugeot SUV models. It was created by the alliance of Mitsubishi, Chrysler, and Hyundai and was used in dozens of other vehicles under different code names.

The construction is classic and very simple. There aren't any lifters. There is no turbocharger in the engine. But in Mitsubishi vehicles, it has MIVEC phasers. Also, the cams are driven by the chain. Fortunately, the engine appeared to be pretty good in terms of fuel consumption and this allowed it to be actively used for such a long time.

Key features and my opinion:

• Production years:2006-now
• Average lifespan of 4B11:220,000-240,000 miles
• Fuel supply type:port injection
• Power range:145-155 hp
• Fuel efficiency:good
• Engine block material:aluminum
• Engine reliability score:high
• The most common problems:oil consumption, timing chain stretching, weak phasers, oil leaks, noisy work with vibrations.

Mitsubishi 2.0L 4B11T engine

This is one of the legendary engines offered by Mitsubishi. The 4B11T powerplant was installed in the Lancer Ralliart and also the Evolution X. It's the sports-ready high-performance engine that offers great power and even more opportunities for tuning and upgrades.

Basically, this is the reliable and simple 4B11 engine reviewed above, just with a turbocharger attached to it. But Mitsubishi made several serious modifications that allowed these engines to last a little longer than expected.

Mainly, the open cooling system was supplemented with the semi-closed cooling system, the oil injectors were added to the cylinders, and crank bearings were modified seriously. Of course, the addition of the turbocharger is essential to make these engines produce a lot of power.

It's not hard to understand that these engines weren't really fuel efficient and required a lot of attention during maintenance and repair.

Key features and my opinion:

• Production years:2007-2016
• Average lifespan of 4B11T:170,000-200,000 miles
• Fuel supply type:port injection
• Power range:240-445 hp
• Fuel efficiency:awful
• Engine block material:aluminum
• Engine reliability score:medium
• The most common problems:very weak timing chain, failing piston rings, phasers fail quite often, weak pulleys in the drive belt.

Mitsubishi 4DR5 engine

This is the diesel engine mainly marketed as Mitsubishi Fuso and used in light trucks. I reviewed it because of several requests and so it's a little different from what I usually review in this blog.

This is a diesel engine with indirect injection and without a turbocharger. In the final version of the 4DR5, Mitsubishi added a turbocharger and changed the construction for more power and higher torque.

These engines were eternal and could run as long as you would want them to. Just proper maintenance and repair would probably allow these machines to last more than 500,000 miles and beyond.

Key features and my opinion:

• Production years:1975-1998
• Average lifespan of 4DR5:400,000-500,000 miles
• Fuel supply type:indirect injection / direct injection
• Power range:80-100 hp
• Fuel efficiency:average
• Engine block material:cast-iron
• Engine reliability score:high
• The most common problems:injection system issues, cooling problems, excessive vibrations, ignition issues.

Mitsubishi 2.5L PR25DD engine

The 2.5L engine used in the Mitsubishi Outlander is actually not a Mitsubishi-engineered powerplant. It's made by Nissan and bough by Mitsubishi to be installed under the hood of the SUV.

The engine is pretty technological but yet reliable and can be considered good in comparison with some competition. There are no lifters to adjust valves, so the valve adjustment will sometimes need to be paid for. Both camshafts have phasers, the cams are driven by the chain.

The engine is naturally aspirated, there is no turbocharger. The company didn't squeeze a lot of power from the 2.5 liters of displacement to leave room for longevity.

Key features and my opinion:

• Production years:2018-now
• Average lifespan of PR25DD:190,000-220,000 miles
• Fuel supply type: direct injection
• Power range: 184-188 hp
• Fuel efficiency: good
• Engine block material: aluminum
• Engine reliability score: medium
• The most common problems: start-stop glitching, carbon buildup on intake valves, EGR valve contamination, no hydraulic lifters.