Why You Should Change Spark Plugs Sooner On Your Turbocharged Engine

A turbocharger is a turbine-driven, forced induction, mechanical device fitted to a vehicle's engine, and it helps in improving the efficiency and power output of an engine. Compared to naturally aspirated engines, turbocharged engines generate increased power output by about 30% to 40%, and they can be used on both gasoline and diesel engines. A significant difference between a naturally aspirated engine and a turbocharged engine is the air entering the combustion chamber. A turbocharger is bolted to the exhaust manifold of the engine where the exhaust gases fall on the turbine of the turbocharger and rotate it. Connected to the turbine via a shaft is a compressor, which pulls atmospheric air and compresses it before supplying it to the intake manifold. The turbocharger forces more air into the engine, which packs in denser air with more oxygen molecules. In proportion to the increased density of air, the vehicle’s ECU adds more fuel into the combustion chamber, which increases the power generation.

The increased power and efficiency offered by the turbocharger have a downside to it as well. Adding a turbocharger to an engine makes it work harder and increases the pressure and temperature inside the combustion chamber. This results in increased strain on the internal components of the engine, including piston, valve, head gasket, and spark plugs. The harder the engine works, the quicker it wears out. Furthermore, increased temperature also deteriorates the engine oil faster than a naturally aspirated engine. All these factors eventually call for shorter service intervals and increased maintenance. It is necessary to carry out periodic checks and maintenance to avoid things like low engine levels, poor-oil quality, or extended oil change intervals.

A spark plug provides the spark necessary to combust the air-fuel mixture inside the combustion chamber. Often the spark plugs are overlooked because they keep on performing for long periods of time without major issues. Spark plugs are small components but are very important for the overall engine performance. When a spark plug wears out, you may experience jerking, engine misfiring, and a significant decline in the fuel efficiency of the vehicle. They are also susceptible to fouling, which can lead to other symptoms, like engine heating due to misfiring and, in worst cases, the meltdown of the catalytic converter. If you have a turbocharged engine, you will have to replace your vehicle’s spark plugs sooner as compared to a naturally aspirated engine. 

The reason for changing spark plugs sooner on a turbocharged engine is due to the increased temperature and pressure generated by the turbocharger. This increased pressure and temperature cause the spark plug to deteriorate quickly compared to engines without a turbocharger. If not replaced, the spark plug won't be able to provide an adequate spark. Due to this, combustion of the air/fuel mixture will be incomplete, leading to a loss in power and knocking. This can further damage other components of the engine and lead to costly repairs.  

Dodge recommends changing your spark plugs every 45,000 km on their turbocharged Dart's engine. Hyundai Sonata and Santa Fe, with their 2.0-liter turbocharged engines, have spark plug changes recommended at 70,000 km or three years compared to 160,000 km on a naturally aspirated engine. Hyundai also recommends an oil change every 8000 km or at least twice a year for their turbocharged variants. You can clearly notice the difference in maintaining schedule and spark plug change intervals for turbocharged and standard vehicles. Of course, the maintenance also depends on driving styles, how much you floor the throttle pedal and other factors. The more stress you put on an engine, the more maintenance it will need.

Manufacturers are leaning towards turbocharged vehicles that can deliver high power with small capacity engines. This makes preventive maintenance essential to keep the engine in great shape. As a responsible car owner, if you are buying a turbocharged vehicle or you already own one, it is important to check and replace your spark plugs regularly. With advanced metallurgy used in designing the spark plugs, they can deliver better performance and sustain high pressure and stressful conditions on turbocharged engines. For example, Iridium spark plugs are stronger than conventional copper and platinum spark plugs, with a melting point of 700° Celsius. You can refer to our comprehensive spark plug buying guide to find the best-suited spark plug for your vehicle and get efficient and reliable performance.