The 3 Most Common Mazda Skyactiv-G 2.0 Engine Problems

Mazda first released the 2.0 Skyactiv-G engine in the 2012 Mazda3. It remains in a handful of popular Mazda models to this day. The 2.0L inline-4 doesn’t have much power, but it offers an excellent combination of efficiency and reliability. Even though the engine is close to flawless there are a few issues to discuss including low oil pressure and carbon build-up. In this article, I discuss these issues with the Mazda 2.0 Skyactiv engine as well as overall reliability.

2.0 Skyactiv Engine Problems

• Low oil pressure
• Carbon build-up
• Nothing*

We’ll discuss the above topics through the rest of this article. However, it’s a good time to add a few quick notes. The Mazda 2.0L engine appears to be highly reliable thus far. We’re calling these the MOST common problems for a reason. It doesn’t mean they’re truly common and affect a large number of 2.0 Skyactiv engines. Rather, when the rare problems occur these are a few common areas.

*We’ve never really run into this situation before, but there just aren’t many problems to discuss. As such, in the 3rd section we’ll just chat about some general concepts regarding reliability. Anyway, the Skyactiv 2.0 engine is definitely among the most reliable engines we’ve ever written about.

1) Low Oil Pressure

Low oil pressure might be the single most common problem on the Mazda 2.0L engine. Even then, low oil pressure issues only affect a small number of Skyactiv engines. It also primarily affects earlier 2012-2014 engines. It’s usually the oil pump that’s to blame for low oil pressure. Specifically, some sort of object or debris stuck on the oil pump pressure relief valve. Mazda issued a TSB to address this problem.

In most cases it seems to be a pretty minor issue as it only causes a small deviation from normal oil pressures. When this occurs it’s unlikely to cause any concerns for long-term reliability. However, it could be cause for concern if too much pressure is lost or the problem isn’t addressed in a timely manner. Running with poor oil pressure for long periods may cause premature wear.

Main bearings and rod bearings typically take a lot of abuse if the 2.0 Skyactiv loses too much oil pressure. It’s unlikely any problems develop in the short-term. However, bearing wear could lead to premature engine failure. This isn’t meant to scare anyone since oil pressure issues aren’t too common, and severe loss of pressure is even less common.

Skyactiv-G Low Oil Pressure Symptoms

• Check engine light (MIL)
• Codes P0015 and/or P0524

Unfortunately, the Skyactiv-G engine does not have an oil pressure light on the dash. However, the computer will trigger a check engine light if oil pressure drops to low. Mazda refers to the check engine light as MIL (malfunction indicator lamp). This will be accompanied by DTC P0015 and/or P0524.

Oil Pump Replacement

When the low oil pressure problems occur, Mazda recommends replacing the oil pump. They also suggest replacing the oil strainer and cleaning the oil pan. This hopefully helps eliminate the chance of any issues happening again as any debris should be removed.

Depending on the specific model labor comes in around 1.5 to 4 hours. The 2014 Mazda3 models are on the longer end of labor while 2012 and 2013 Mazda3’s are quicker. The cost of parts will add up to an extra couple hundred dollars, too. As such, expect 2.0 Skyactiv-G oil pressure problems to cost about $400-800 to fix at a repair shop.

2) Carbon Build-Up Problems

Alright – we’re already moving onto something we don’t consider a true problem. However, direct injection (DI) engines like the 2.0 Skyactiv-G are prone to carbon build-up on the intake valves. All engines have some degree of oil blow-by that makes its way into the intake ports.

With port injection fuel is sprayed into the intake ports and that helps wipe away any deposits. However, DI sprays fuel directly into the Mazda 2.0 cylinders so there’s nothing wiping off the ports or valves. Over time, oil can stick and form chunks of carbon deposits. Direct injection has tons of benefits, but this is one small drawback to the technology.

Fortunately, modern engines have great PCV systems to help reduce oil blow-by. This doesn’t completely eliminate carbon build-up, but it does help slow the problem. Expect excess carbon build-up to potentially cause trouble in the 80,000 to 120,000 mile ballpark.

It’s not an urgent issue, though. Some 2.0L Skyactiv engines will go their whole lives without any intake valve cleaning. However, in some cases, carbon deposits can cause a handful of symptoms and drivability problems.

Mazda 2.0 Carbon Build-up Symptoms

• Misfires
• Rough idle
• Power loss

As carbon deposits form they begin to restrict air-flow into the cylinders. That can cause symptoms like engine misfires, rough idle, hesitation, etc. Carbon build-up will also cause the 2.0 Skyactiv engine to lose power. Although, it’s likely hard to notice since it occurs over a period of years rather than a sudden loss of power.

Carbon Build-up Fix

Walnut blasting remains one of the most effective way to clean the intake valves and ports. It involves a heavy duty shop vac and walnut media shells. Of course, the 2.0L Skyactiv intake manifold must be removed to access the ports. Once in there the actual cleaning process can take an hour or two depending how bad the valves are.

Anyways, the job is mostly labor and most shops will charge somewhere around $300-600 for Mazda 2.0 walnut blasting. Some opt to install an oil catch can and use certain chemicals in the intake to help prevent deposits from forming. Though, once excess carbon build-up is there walnut blasting is the most effective method to truly clean the valves.

3) General Reliability Considerations

Well, there really isn’t much else to discuss in terms of known issues or design flaws on the 2.0 liter engines. Many modern engines rely on turbochargers for power, or simply get as much out of a naturally aspirated design as possible. Mazda 2.0 Skyactiv-G engines use plenty of modern tech, but output per liter is fairly low.

That’s not a bad thing, though. It’s a big reason the 2.0L Skyactiv is able to deliver excellent reliability and fuel economy. Low oil pressure is really the only true problem we brought up in this article. It’s still a fairly uncommon problem, but Mazda did issue a Service Bulletin regarding low oil pressure issues. Otherwise, carbon build-up is a small price to pay for direct injection which is otherwise awesome tech.

We could have come up with a 3rd problem for the engine, but we haven’t seen large numbers of owners run into the same problems. That said, cars and engines use thousands of different parts from varying manufacturers. Defects happen from time to time and it’s rare a car sees 10-15+ years and 150,000+ miles without at least a minor problem or two along the way.

Point is – the 2.0 Skyactiv engine isn’t bulletproof and 100% flawless. It is an amazing engine all around, though. Regardless, as early models continue aging it’s likely more problems come to light due to natural wear and tear.

Mazda 2.0 Skyactiv Engine Reliability

Is the Mazda 2.0L engine reliable? Well, we certainly haven’t made it a secret how we feel about this engine so far. We definitely believe the 2.0 Skyactiv engine earns well above average remarks for reliability.

There isn’t a totally perfect mass production engine in the world, but the Mazda 2.0 is definitely up there with some of the best. It doesn’t suffer from any serious design flaws or countless common problems. As a small NA engine maintenance is also easy on the 2.0 Skyactiv-G engine.

Some Mazda 2.0L Skyactiv engine reliability simply comes down to the luck of the draw. However, maintenance is one key component owners have control over. Maintain the engine well – use quality oils, change fluids on time, and fix problems if and when they occur. Do this and most will have a rewarding and reliable experience from the Mazda 2.0 engine.

Looking for more on the Skyactiv-G and Mazda? Check out some of our additional content including this MX-5 Miata Buyer’s Guide, Mazda3 intake upgrades, and more.