As the world’s second-largest automobile company, Volkswagen is leading the drive towards more powerful and capable engines, introducing many innovative new technologies and features to the market.
One such development is TFSI engine technology.
Since their introduction, TFSI engines have become a staple of Volkswagen’s product range. You’ll find the TFSI badge on many vehicles from VW’s stable of models, including other brands owned by Volkswagen Group such as Audi.
This technology has gone through several revisions since it was first introduced to the Audi product range in 2004 market. Today, it can be found in all sorts of Audi models, ranging from the high-performance RS 7 all the way down to A3.
Combining higher power output and superior engine response with reduced emissions and improved fuel efficiency, it’s little wonder that TFSI technology is now standard on the vast majority of new-build Audis. It has even earned Audi several engine of the year awards.
Unfortunately, certain TFSI engines suffered from a specific defect that could severely impact engine performance and affect oil consumption. Many of our clients who call in for Audi service in Melbourne call in with this particular issue.
Do you own an earlier TFSI engine? Worried your car might be susceptible to this issue? Today, our Audi mechanics in Melbourne explain exactly what the issue is, which vehicles were affected and how we can fix the problem for you!
A quick recap: what is TFSI technology, and how does it work?
As we’re sure you know, the benefit of direct fuel injection systems like Audi’s FSI system is increased fuel efficiency, improved power output and reduced emissions.
By injecting fuel directly into the combustion chamber rather than into the intake manifold as with a traditional engine, FSI engines allow for higher compression and more power, even with a leaner air / fuel ratio .
TFSI (turbo fuel stratified injection) technology marries the principles of FSI engines with the power of turbocharging to create an even more powerful and efficient engine.
By pairing turbo technology with direct fuel injection, TFSI engines enable small-displacement engines to punch above their weight by dramatically increasing the amount of energy that can be created and captured.
This combination also resolves one of the oldest problems with turbocharged engines: knock.
When air or any other gas is compressed, its temperature will rise. By supplying even more compressed air directly into the cylinder, turbocharged engines can raise the pressure (and therefore the temperature) so high that the fuel/air mixture combusts prematurely, impacting efficiency and causing damage to your engine.
When this fuel evaporates, it reduces temperature – this is the principle behind air conditioning.
FSI direct injection minimises fuel loss by spraying fuel directly into the chamber. That translates to a richer fuel mixture in the chamber, which in turn means more evaporation and a greater cooling effect.
Together, this allows Audi to create turbocharged engines with dramatically lower risk of knock.
An Audi mechanic in Melbourne explains the problem with pre-2012 2.0L TFSI engines
The problem with operating at the cutting edge is that it’s very easy to slip off and cut oneself, so to speak!
As the first car manufacturer to produce combine turbo and direct fuel injection, early TFSI engines suffered from an inherent design fault which affected the consumption of motor oil.
Specifically, the issue is that many 2.0L TFSI engines manufactured before 2012 consumed too much motor oil!
This particular engine is one of the most widely-used engines, and can be found in A5, A4 and Q5 vehicles, just to name a few.
It’s normal for some motor oil to be used up as you drive. According to the Audi specification for the 2.0L TFSI engines, the maximum oil consumption rate is 0.5 litres every 1000km – an extremely generous figure that very few drivers will experience. In many cases however, owners of Audis powered by these particular engines saw their motor oil being used up at even higher rates than this.
As we’re all aware, motor oil is the lifeblood of your engine, responsible for lubrication, cooling and cleaning, among other things. Low oil levels can impair engine performance and even result in permanent engine damage if the oil isn’t replaced in a timely matter.
Not to mention, it can also be quite costly having to replace your oil on a monthly basis!
This isn’t because of poor engineering. Rather, the most common issue is with one particular part: specifically, the piston rings.
Piston rings are metal rings that wrap around the piston, sealing the combustion chamber. In addition to the 2 compression rings, there is a third oil control ring, that prevents engine oil from the crankcase entering the combustion chamber.
As we’re sure you can tell by today’s topic however, pre-2012 used piston rings that were prone to premature wear.
Early 2.0L TFSI engines used small 1.5mm piston rings to minimise friction as the piston goes up and down. Owing to their relative thinness and fragility however, our Audi mechanics in Melbourne have seen many of these narrow rings wear causing excessive oil consumption.
The consequences of this were twofold:
- It resulted in gases escaping from the combustion chamber, which led to a corresponding loss in engine power.
- This also allowed small amounts of motor oil to get into the combustion chamber, where it would burn up, leading to high oil consumption.
Making the problem even worse, the bore was often vertically-hatched on the inside rather than the traditional 45-degree hatching in order to reduce friction as the piston moves up and down.
Unfortunately, the vertical hatches also had the side effect or providing tiny channels for oil to get past the piston rings and into the chamber!
Why you can’t ignore the problem
Many Audi owners were content to simply top up their oil whenever the warning light came on. While not ideal, it would certainly be cheaper than getting the engine repaired by an Audi mechanic, they tell themselves.
Over time however, it became clear that this was a problem that could not be ignored.
In particular, it was noticed that this problem often resulted in scoring and grooves in the cylinder bores, which further increases the amount of motor oil that leaks into the combustion chamber.
Without intervention from an Audi mechanic in Melbourne, the time between oil top-ups will continue to get progressively shorter thanks to this scoring, burning a considerable hole in your wallet.
In addition to costing money however, oil in the combustion chamber can drastically affect your Audi’s engine performance and fuel efficiency.
Your Audi may run rough as a consequence, and your spark plugs becoming fouled by oil. Thoroughly coated plugs can even fail to ignite the air/fuel mixture altogether, leading to regular misfires. You may even detect the vehicle blowing blue smoke, or the rear of the vehicle being covered with a thin film of oil.
Is there a fix?
Around 2012, Audi updated the spec on the pistons used in the affected engines. Newer TFSI engines make use of a revised piston design which upgraded from a 1.5mm piston ring to a more durable and sturdier design that features rings 2.5mm thick.
Thanks to the increased thickness, the new pistons are much less likely to leak oil into the combustion chamber, which has had the effect of dramatically reducing oil consumption and allowing you to go longer between oil changes.
Additionally, Audi also changed the manufacturing processes for the bores. Newer engines use bores with horizontal hatching to eliminate potential pathways, reducing the amount of motor oil that’s able to get into the combustion chamber.
Although it is a time consuming repair, revised pistons can be retrofitted into existing Audis with 2.0L TFSI engines showing signs of oil consumption.
Owing to their location in the heart of your engine, getting this job done is a fairly involved process.
The engine and transmission need to be completely removed from the vehicle, and the engine completely disassembled. The entire repair necessitates a large amount of skilled labour, along with an array of specialised equipment, including model specific tooling, an engine removal crane and rebuild stand.
This isn’t the type of repair you can do on your own. Additionally, German cars like those from Audi typically feature many other unique or proprietary features, which can make it hard for a generalist mechanic to properly diagnose and fix issues such as these.
Concerned? Call our Audi mechanics in Melbourne
If you’re looking to purchase a second-hand Audi. You’ve also heard about this problem, and are worried that the car you’re looking at may be afflicted with this particular issue.
Don’t let this problem stop you from buying that Audi – you could be missing out on a fantastic deal!
In addition to providing regular maintenance, our Audi mechanics in Melbourne also perform pre-purchase inspections for those who are looking to purchase a second-hand vehicle.
As German car specialists, our checks are considerably more in-depth than at a general mechanic. Not only are we aware of these unique issues, but we’re also intimately familiar with the unique features commonly associated with Audis.
Our pre-purchase inspections go into depth, and can uncover a great deal about the car you’re looking at buying. In addition to diagnosing whether or not your TFSI engine is presenting with these problems, we can also identify:
- A poor service history
- Bad accident repairs
- Dodgy routine services
- Low-quality aftermarket parts
- Problems the seller might be trying to hide
It’s a relatively small investment compared to buying a second-hand car. However, it’s completely worth it – we can save you from making a purchase you may regret later!
Choose Ammstar Autohaus for ongoing (and affordable) Audi service
And once that purchase goes through, you’ll still need to take your vehicle in for regular Audi servicing.
Looking for a specialist Audi mechanic in Melbourne? You’ve found it in Ammstar Autohaus!
Our team provides in-depth service for the entire Audi range, as well as many older models from the manufacturer with four rings. We also provide specialist services for vehicles from other high-end German automakers, including Mercedes-Benz, Volkswagen and BMW.
And to top it all off, we’re able to offer all this at a superior price compared to the dealership. Our mission is to bring down your Audi service cost, whether it’s a pre-purchase inspection, a routine service or a deep repair.
Give us a call today:
Alternatively, click here to book a Audi service online.