Subaru FB16 1.6L Engine Specs, Problems, Reliability, Info

Subaru 1.6L FB16 Overview

The Subaru 1.6-liter FB16/FB16B was introduced in 2011 as a new engine for the 2012 model year Subaru Impreza XV. This is a naturally aspirated four-cylinder gasoline boxer engine from the latest Subaru FB engine family. The FB series also includes the 2.0L FB20 and the 2.5L FB25 engines. This 1.6-liter model was not available in North America, but it is well known in Europe, Japan, and Asia. Let's take a look at how this version compares to other engines in the series, and what its pros and cons are.

FB16/FB16B Engine Design

The FB16 is essentially a smaller version of the FB20. The design of cylinder block is the same: it’s an open deck aluminum cylinder block with cast-iron sleeves. The sleeves are poured into the block during production. The bore and stroke sizes are smaller. The internal components, such as the crankshaft, connecting rods, and pistons, differ from those in the FB20 model. The cylinder heads look similar. This engine also has aluminum DOHC (dual overhead cam) heads with chain-driven camshafts. There are four valves per cylinder, roller rocker arms an no hydraulic lifters. Each camshaft comes with a variable valve timing system, called dual AVCS.

The FB16B features a conventional electronic multi-point fuel injection system and a coil-on-plug, electronically controlled ignition system. The intake manifold is made from a composite material (a special type of plastic) and is fitted with a drive-by-wire throttle body. In order to comply with Euro-5 environmental regulations, the intake of some Subaru models was equipped with tumble generator valves (TGV) above the fuel injectors. The TGV increases the swirl of the air and fuel mixture, which results in a cleaner operation. In addition, this gasoline engine has an exhaust gas recirculation (EGR) system and catalytic converters.

FB16 Turbo

The naturally aspirated FB16 engine became the basis for the first turbocharged engine in the FB series, known as the FB16DIT / FB16F. In addition to this, this turbocharged version also features direct fuel injection. The FB16DIT engine became the base option for the first generation of the Subaru Levorg. The power output is 170 horsepower and 250 Nm (184 lb-ft), which is comparable to that of a larger 2.5-liter FB25 engine.

Engine Specs

FB16 Problems and Reliability

That having been said, it's essentially the same as the FB25 and the FB20. For this reason, they also have almost the same list of problems and breakdowns.

• Firstly, FB16 engines like to eat up motor oil. But to be fair, I must say that this issue is not as extreme as it is with 2.0-liter engines.
• The valve train does not have hydraulic lifters, so it may be necessary to adjust the valves occasionally.
• The phase adjusters of the AVCS are highly sensitive to the quality of the engine oil. It is very important to use only the recommended oil.
• There have been cases of cranking the main bearings due to low oil level. So, keep an eye on the oil level.
• The cylinder block can lose its geometry due to overheating. An open deck block is not very strong on its own.

Summary

Drawing the line, is the Subaru 1.6L boxer engine a good and reliable option? The answer is both yes and no. It depends on many factors: what kind of oil was used, fuel, how often it was maintained, operating conditions, and so on. The estimated engine life of the FB16 seems to be not very long — around 150,000 miles (250,000 kilometers). But in 1600 cc class it is average numbers for these days.