Turbocharged engines have more than proven their worth when it comes to horsepower. The 2026 Volkswagen Jetta gets a respectable 158 horsepower out of a 1.5-liter four-cylinder, and if you want to go even smaller, the Chevrolet Trax gets 137 hp out of a 1.2-liter turbo-three. The technology is there to build potent, capable turbocharged engines half the size of a naturally aspirated V6 or V8.
Building them to last just as long as a larger, older naturally aspirated powerplant, though? That’s another matter.
Switching To A Small Turbo Almost Always Hurts Reliability
2013 Ford Escape Silver Front Angled ViewFord
One of the most iconic examples of a car taking an immediate reliability nosedive after switching from larger naturally aspirated engines to a smaller turbocharged lineup is the Ford Escape. The 2012 model offered a 171-hp 2.4-liter four-cylinder as its base engine, with an optional 3.0-liter V6 producing 240 hp. For 2013, Ford dropped the V6 and added a 178-hp 1.6-liter turbo-four at the base level.
The 2012 model had its share of engine complaints, with over 70 on file with the National Highway Traffic Safety Administration, but the numbers spiraled out of control with the launch of the 2013 model, which generated over 1,200 engine complaints in its first year. These grievances include multiple reports of stalling, loss of motive power, and total failure, with many drivers citing the 1.6-liter unit as particularly problematic.
Some drivers have a single bad experience with a car like this and swear off a brand or nameplate entirely, or at least stick to older models if they can. This is what we’re seeing with, for instance, Tacoma buyers who aren’t happy with the truck’s shift to turbo-fours over naturally aspirated V6 engines.
Small Engines Are More Reliable Without Turbos
Rear quarter view of a 2017 Honda Civic HatchbackHonda
Honda saw a similar trajectory with the launch of the 1.5-liter turbo-four Civic for 2016. The 2015 Honda Civic, powered by a naturally aspirated 1.8-liter four-cylinder, has generated around 30 engine complaints with the NHTSA. The 2016 model has closer to 100 engine complaints, which is a bit high for a Honda.
One driver reports that, in 2022, “one of my vehicle’s pistons flew out the side of the engine and, thankfully, onto the ground, not injuring or killing anyone.” Yes, this is possible, even if it sounds like something that would only happen in a cartoon.
More often than not, you’ll find that, when a nameplate switches from being driven primarily, or exclusively, by naturally aspirated engines to small turbocharged powerplants, you’re going to see a dip in dependability, be it minor or major.
Turbochargers Make Engines Less Reliable
Engine view of a 2017 Honda Civic HatchbackHonda
To be clear, there are also unreliable naturally aspirated engines of all sizes, and there are reliable turbocharged powerplants. But, you can take any engine you like and put a turbocharger on it, and you’re automatically shaving years off its life expectancy. The turbocharging process simply puts more stress on the engine.
To go over how a combustion engine works:
- Air and fuel mix in the cylinder.
- Spark plugs ignite the mixture.
- The controlled explosions push the pistons.
- The pistons push the crankshaft.
- The crankshaft sends power to the wheels.
This process creates exhaust gases, which are released through the tailpipe, and that’s where the turbo comes in.
A turbocharger puts these exhaust gases to work, using them to spin a turbine that compresses incoming air and feeds it into the engine to create a more potent air-fuel mixture.
We’re Talking About Controlled Explosions
Audi S4 Engine Bad PistonI Do Cars / YouTube
The whole internal combustion process depends on, well, internal combustion. That is, you’re setting off hundreds, or thousands of explosions per minute inside a metal block about the size of an Igloo party cooler.
In fact, you can count the explosions-per-minute yourself by dividing the engine’s rpm by strokes (two-strokes fire once for every revolution, while four-strokes fire once for every two revolutions), and multiplying it by the number of cylinders. So a four-stroke V8 running at 2,000 rpm is setting off 8,000 explosions every 60 seconds.
A turbocharger does not increase rpm, but it makes every explosion more potent by cramming more air into the combustion chamber. This applies to almost anything you can do to increase horsepower without adding an electric motor. ECU tuning, for instance, targets the air-fuel ratio to create a more potent explosion in the combustion cylinder and improve performance without physical modifications.
With a turbocharger, the engine runs hotter than a naturally aspirated version of the same engine, subjecting the cylinders to increased pressure and putting added stress on components like the connecting rods. Plus, the turbo system itself has moving parts that can break.
A well-built engine can withstand turbocharging and tuning without immediately falling to pieces, but it would have shorter longevity. An engine block can only take so much pressure for so long before it needs maintenance or repairs, unless it eventually fails.
Longevity Isn’t Always A Priority
2016-2021 Toyota Land Cruiser Mk7 Facelift 2 Gray Front ViewCarBuzz
So, if swapping a big, naturally aspirated engine out with a small turbocharged powerplant is guaranteed to take thousands of miles off of a car’s life expectancy, why do so many automakers insist on doing it?
The truth is, longevity just isn’t a high priority for most automakers, and it isn’t for most drivers either. Most owners don’t keep a car until it stops running. Generally, the vehicle changes hands to a second or third owner before these issues occur.
According to the EPA, a typical American driver puts around 15,000 miles on their car every year. According to iSeeCars, we tend to trade in our vehicles after about eight years on the road, give or take a few months. That means that a driver might put around 120,000 miles on their car before selling it off.
There are some exceptions. Toyota fans are drawn to longevity, and Land Cruiser owners tend to keep their cars for a little over 11 years. Enthusiast types treasure their cars, with Chevy Corvette and Porsche 911 owners tending to keep their babies for a decade or so. But if a car can make it 250,000 miles on the original powertrain, the first driver is unlikely even to reach the halfway point.
If longevity isn’t a big part of a brand’s appeal, it’s actually not that consequential to a car’s success. Turbo problems can hurt a car’s sales when they come in the form of engine failure and steep repair bills before you reach 100,000 miles, but so few drivers ever reach a quarter million miles on the odometer that it doesn’t really matter if a turbocharged powerplant comes with an earlier expiration date than a larger NA engine.
The EPA Likes Turbochargers
Porsche 911 Turbo S rearPorsche
If you’re ever talking cars, and you run out of things to say, just blame something on the EPA, it’s probably their fault. Turbos might not be great for engine longevity, but they are good for the environment.
The turbocharger itself can improve fuel economy by 10% or more. Additionally, a small turbocharged engine can shave hundreds of pounds off of a car’s curb weight, further improving fuel economy and reducing emissions. All of this helps automakers to get their emissions within mandated allowances.
There Are Plenty Of Reliable Turbocharged Engines Out There
Overhead shot of a 1997 Toyota Supra TurboBring A Trailer
We can go on all day listing reliable turbocharged engines, to be honest. The twin-turbo Toyota 2JZ-GTE is more dependable than the vast majority of naturally aspirated six- and eight-cylinder engines out there. Turbodiesels like the Cummins 5.9-liter 6BT are especially durable, with some clearing more than a million miles.
But the bottom line is that these engines won’t reach the same mileage they would if you were to remove the turbochargers entirely. Turbochargers put more stress on the engine as a rule. If you’re lucky, that won’t become a problem until you’ve already passed 200,000 miles, but sooner or later, it will become a problem.
Sources: Honda, Ford, Chevrolet, NHTSA, FuelEconomy.gov.
