Turbochargers are rather genius inventions that recycle waste exhaust gas to boost engine power, allowing for smaller, lighter engine design and increased overall fuel efficiency. Even though it sounds relatively straightforward, adding a turbo to an engine comes with its own set of problems. After all, it’s another component that requires maintenance. It also has a pretty intimate relationship with the engine, so trouble for one can mean trouble for both.
As with most things, turbo engine failure gets worse the longer it remains unchecked. Consider the following signs and causes of failure if you’re looking to get the most out of your turbo.
Why Turbochargers Fail?
Perhaps the most common mistake is to view a turbocharger as an add-on component to an engine, like one would an alternator. Therefore, many people assume, when the turbo fails, it is the turbo’s fault and a new unit is needed. In truth, the vast majority of turbo failures are due to external factors. Have a look at the list and statistics below, provided by Turbo manufacturer Yuuhatsu.
Insufficient lubrication - Contributing to 40% of failures
• Oil Starvation
• Deformed, bent or clogged oil lines
• Undersized oil filter
• Dirty oil filter
• Contaminated oil
Foreign objects into turbine - Contributing to 25% of failures
• Pieces of burned valves
• Pieces from broken combustion cups
• Casting fins from manifolds
• Chips from exhaust ports
• Pieces from scuffed and broken pistons
• Improperly installed gaskets
• Nuts and washers dropped into the exhaust system
Foreign objects into compressor - Contributing to 15% of failures
• Pieces of the broken or loose air filter
• Pieces of rubber or wire from the air intake hose
• Nuts, bolts and washers dropped into the intake system
Excessive heat and over boosting - Contributing to 15% of failures
• Improperly de-rated at high altitude
• Incorrect timing
• Reduced air inlet caused by clogged air filter, and collapsed hose
• Air leaking at air intake
• Leak from exhaust pipe
Improper handling and installation - Contributing to 5% of failures
• High loads applied to turbo housings due to improper piping
• Excessively heavy piping that is supported only by the turbocharger
• Excessive vibration due to improper mounting
• Turbocharger being dropped onto shop floor
• Holding the actuator as the handle
As is evident above, the majority of turbo failures are due to external factors. It follows therefore, that these factors have to be addressed before fitting a new turbo, or the new turbo will suffer the exact same unfortunate fate.
The Warning Signs
As with most components that make up a vehicle, turbos are not immune to failures nor breakdowns. Below, we explore six common symptoms of turbo problems, so you can tend to them before any further damage is done to your vehicle.
1. Poor acceleration/ Loss of Power - One of the most significant symptoms of a failing turbo you should notice is lack of overall power. The car may appear sluggish and not accelerate quickly or produce the usual amount of power while on the road.
2. Irregular or excessive exhaust - A crack in the turbo housing, or seals which have worn out, can cause oil to leak into the exhaust system. When this leaked oil burns, it will result in characteristic blue or grey smoke. This smoke is more visible when the turbo is running. Hence, if you notice excessive smoke when revving the engine, chances are your turbo is faulty.
3. Increased Oil Consumption - If you notice that your car is using more oil than usual, it could be an indication that your turbocharger is leaking oil into the manifold. It can eventually lead to oil starvation and to the turbo failing.
4. Check engine light - While the “check engine” light is an all-encompassing warning sign that will not point specifically to anyone mechanical issue, it can signify a turbo fault or failure. An illuminated check engine light should never be ignored and indicates further inspection is necessary to determine whether a repair or replacement of the turbo is required.
5. Lack of boost - Some of the turbochargers, more likely sports cars, have a boost gauge, which displays the amount of boost that the turbo is producing. If your car is one of those, then you can just look at the boost gauge to determine if the turbo is creating the right amount of boost and if it is rising much slower than usual, a replacement turbocharger may be necessary.
6. Loud shrieking noise - If a turbo is failing, it may produce a noise when the boost is running. The noise comes directly from the engine and sounds like a loud siren or shriek, which tends to get louder as the problem worsens. Any unusual noise under the car’s bonnet is worth investigating, especially if the sound accompanies any additional turbo failure symptoms.
Turbochargers, like all mechanical components, have a life span. A life span which can be prematurely cut short by insufficient lubrication or the ingress of foreign objects. Should your turbo fail, the cause of failure must always be identified and rectified before fitting a new turbo.At Start My Car, we have a comprehensive range of replacement D.O.E turbochargers, which are interchangeable with your OEM turbo. As always, have a look on our website, or contact us if you are unable to find it online, and we would be more than happy to assist you.