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Audi’s TT MK2, also referred to as Type 8J, was the successor to the MK1 TT and was 5 inches longer and 3 inches wider. The TT MK2 was first introduced in 2005 at the Tokyo Motor Show and was produced from 2006 – 2014. It was built on the Volkswagen PQ35 platform and was available in a 2+2 coupe or two-seat roadster. There were multiple trims that were available: TT, TTS, and TT-R. Audi’s TT MK2 was awarded many awards in its production cycle: Drive Car of the Year, Top Gear Coupe of the Year, Autobild Most Beautiful Car, World Design Car of the Year, and a finalist for World Car of the Year.
Audi TT MK2 Engines
There were many engines that were featured in the second generation TT, four gas engines and one diesel engine. To start it off, the 8J TT featured an EA888 1.8 TFSI that put down 158hp and 184lb-ft. More gas engines available were: an EA113 2.0 TFSI (197hp/207lb-ft), an EA888 2.0TFSI (208hp/258lb-ft), 3.2L V6 VR6 24v (247hp/236lb-ft), and finally a 2.5 R5 turbo (335hp/332lb-ft) that is only found in the TT RS. There were options of a 6-speed manual and 6-speed S-Tronic automatic transmission. The most common engines for this generation were the 2.0 TFSI’s.
For the diesel engines, there was only one to choose from and it came to the European market in 2008: 2.0TDI quattro® that put down 168hp and 258lb-ft of torque. The only transmission available for the TDI was a 6-speed manual.
Before jumping into the common problems, we’ll try to identify what specific engines the problems are for. However, we will list replacement parts below, please make sure the parts fit your vehicle.
Common Audi TT MK2 Engine Problems
- Ignition coil pack failure
- HPFP failure
- Diverter valve failure
- Carbon buildup
- Excessive oil consumption
- Knocking steering rack
- Power window regulator failure
1. Ignition Coil Pack Failure
Ignition coil packs, unfortunately, are the most common problems when it comes to Audi engines. They transform the battery’s 12 volts into the 20,000+ volts spark plugs need to create a spark in the combustion chamber and initiate engine combustion.
The two main reasons they fail are normal wear and tear or engine modifications. Whenever you modify the engine of a vehicle, the factory coil packs can’t sustain the increased power. When we say modifying an engine, we aren’t referring to basic bolt-ons, we are talking about tuning. When a singular coil pack fails, the vehicle will experience misfires in a specific cylinder. However, when there is more than one faulty, the engine will have a hard time starting and the engine performance dampened substantially. A general rule of thumb is to change coil packs out every 60,000 miles but with a modified engine every 40,000 miles.
Symptoms of Coil Packs Failure:
- CEL/MIL illuminating with P0300 – P0306 fault codes
- Engine misfires
- Decreased engine performance
- Having trouble turning the engine on
- Engine surges or stalls
When ignition coil packs go out, whether it be a single coil pack or multiple, we highly suggest changing out all of them at the same time. If you were to only change one, it could cause a headache trying to find the faulty coil every few months. This is a pretty simple DIY and we would honestly suggest changing the spark plugs as well. A local dealer or mechanic would charge around $250 to replace the coil packs.
2. HPFP (High-Pressure Fuel Pump) Failure
HPFPs, or High-Pressure Fuel Pumps, fail quite often in Volkswagen’s and Audi’s, however, the 2.0 TFSI engine is what we will be focusing on. In this case, it’s not usually a faulty HPFP, it’s the cam follower that causes the HPFP to fail. As it sounds, an HPFP pumps high-pressure fuel into the direct injection system. A cam follower is essentially a buffer part that goes between the camshaft and HPFP to ensure the two components don’t rub together.
Again, the HPFP doesn’t usually fail, but the faulty cam follower prematurely wears causing the HPFP to fail. However, if you have or are wanting a heavily modified engine, we would advise upgrading the HPFP because the factory ones could fail with more power. When this happens, it could cause major engine damage because then the HPFP and camshaft will begin to rub together. We’ve seen many 2.0TFSI consumers look at cam followers for regular maintenance because the part is so inexpensive compared to what would happen if it prematurely wears. We would highly suggest replacing the cam follower every 50,000 miles at a minimum.
Symptoms of HPFP Failure:
- CEL/MIL illuminating with fault codes: P0087, P0192, or P2293
- Poor engine performance, specifically rough acceleration
- Metal clanking in the engine bay
If the cam follower fails and the HPFP and camshaft start rubbing, you will more than likely have to replace the HPFP and the intake camshaft. However, if you stay on top of checking the cam follower regularly, not only will engine damage be minimized, but engine longevity will be longer as well. We’ll link a video of how to replace the cam follower on a 2.0 TFSI down below to show how easy it can be to change and check. To replace a cam follower, a mechanic would charge around $150 depending on labor rates. However, to change the HPFP and intake camshaft, you’ll be looking at a much more costly repair.
Buy Here: TT MK2 Cam Follower Replacement
DIY Difficulty: Easy
3. Diverter Valve Failure
Diverter valve, often referred to as just “dv”, failure is another common problem that is specific to the 2.0 TFSI engines. A diverter valve is a pressure release valve, located on the side of the turbo, that “diverts” unused pressure back into the system to avoid compressor surge. In simple terms, it releases boost pressure when the engine’s throttle body closes.
The main reason these fail on 2.0TFSI’s is due to the diaphragm ripping. When the dv valve fails, boost pressure will be lost and compressor surge will occur. You will want to address this issue right away as the engine will not run smoothly until it is fixed. Dv valve is not a regular occurrence unless it is on a modified engine with a tune. The more power the engine puts out over the factory power, the less likely the factory dv valve will hold the boost pressure. However, if you don’t plan on modifying the engine, you shouldn’t have to worry about these failing more than once.
Symptoms of Diverter Valve Failure:
- Sluggish performance
- Too lean or too rich AFR conditions
- Rough idle
- Premature boost pressure loss before letting your foot off the gas
There are really only two options when it comes to dv valve failure: if the diaphragm ripped, you will have to replace it, or if it fails due to a modified engine, you will have to get an upgraded dv that will be able to sustain the increased boost pressure. It’s not a terribly difficult DIY if you know where the part is, pictured above. In 2.0TFSI’s, It is at the bottom of the turbo and must be accessed from beneath the vehicle.
Buy Here: TT MK2 Diverter Valve Replacement
DIY Difficulty: Intermediate
4. Carbon Buildup
Now, these next two problems are very common in the 1.8 TFSI and 2.0 TFSI. However, carbon buildup is something that occurs in every direct injection engine nowadays. It is something that can be prevented, but not totally done away with. So what is carbon buildup exactly? With direct injection, fuel is sprayed directly into the combustion chambers through the intake valves. Over time, carbon will start to build up from all of the fuel the intake valves see naturally causing oil deposits/soot. The more buildup in the intake valves, the harder it is for the engine to “breath”. As minor as it may seem, this can severely dampen an engine’s performance.
This is more common in vehicles that are used only for short commutes to work, store, etc on a daily basis. The longer an engine is run, the hotter it gets, and is able to burn off the buildup in the intake valves. Issues will start to be seen anywhere from 30,000 – 60,000 miles.
Symptoms of Carbon Buildup:
- Cold start misfires
- Poor engine performance
- Engine knocking
- Decreased fuel economy
Ways to Prevent Carbon Buildup:
- Replace spark plugs regularly
- Use premium quality fuel (93+ Octane)
- Get scheduled oil changes
- Manually cleaning the valves every so often
- Using an oil catch can
- Run the engine hard regularly
- Sea foam or other chemical
5. Excessive Oil Consumption
Excessive oil consumption is the main reason the EA888 engines, 1.8 TFSI and 2.0 TFSI, have a bad rep when it comes to reliability. As it sounds, this means the engine is “guzzling” oil at a quicker rate than the acceptable range supplied by Audi. This unfortunately is a symptom of a failing PCV valve as well only unless you notice a whistling noise coming from the engine, lean or rich AFR conditions, or P0507/P0171 fault codes. If your MK2 TT has a 1.8 or 2.0, we would advise taking it into the shop if it seems like your engine is guzzling oil.
If ignored anytime before 50,000 miles, this can be very costly. Apparently, some engines out of the factory were fitted with piston rings that were too thin. What this resulted in were oil leaks. We’ve seen customers pay up to $6,000 in engine repairs because the pistons and piston rings will need to be replaced.
Symptoms of Excessive Oil Consumption:
- Oil deposits on the engine
- Blue smoke emitting from the exhaust
- Low engine oil indicator on more than normal
- Metal shavings in the oil pan
- PCV valve failure
A good rule of thumb if your vehicle is experiencing this, go to the shop and ask for a compression test. This should tell them if there is something wrong with the internals of the engine, pistons, piston rings, etc. If your vehicle is experiencing the PCV valve symptoms listed above, replace it first and see if it alleviates the engine from guzzling oil. If not, take it to a shop ASAP.
6. Knocking Steering Rack
The next two problems are not engine specific, but they are annoying enough to put on this list. What do we mean when we say “knocking steering rack”? Some MK2 TT owners have complained about a knocking or clicking noise coming from the front of the car, video clip linked below, when turning continuously and slowly. Come to find out it is a common problem in the top of the steering rack. Since the MK2 TTs have been out since 2006, hopefully, most of them out there have been resolved.
Back when warranties would have been useful, the steering rack would have been replaced under warranty. However, given that it has been 15 years since these were first produced, warranty work on the steering rack may vary from dealership by dealership. With that said, it should not affect the function of the vehicle. So if the noise doesn’t bother you, it SHOULD be okay in most cases. Our advice, is to get it looked at anyways because this is not normal to MK2’s.
7. Power Window Regulator Failure
Another very annoying, and unfortunately common, problem in Audi and VW’s is power window regulator failure. Customers have been complaining about windows being stuck up or stuck down and, as you can imagine, this is not only a hassle for you but it’s just annoying. Power window regulators contain the window glass in two channels and make the window go up or down with the push of a switch. These regulators shouldn’t fail at all throughout the lifecycle of a vehicle, but some in the MK2 TTs seem to be faulty out of the factory.
Symptoms of Power Window Regulator Failure:
- Window stuck up or stuck down
- Slower or faster than normal window scrolling speed
- The window is not level/crooked
- Multiple presses on the power window switch before moving the window
When the power window regulator fails, it will have to be replaced with a new part. This replacement is not the hardest DIY, it is just tedious since the door panel will have to be removed. The part is not cheap if the OEM part is ordered, but you can find cheaper ones online. A DIY would save you around $250 in labor costs.
Buy Here: TT MK2 Power Window Regulator Replacement
DIY Difficulty: Easy
Audi TT MK2 Reliability
As you can imagine with all of the awards the Audi TT MK2 won in the past, this vehicle is extremely reliable pending regular maintenance. Specifically, manual transmissions are more reliable than automatic transmission TTs. As far as which engine is the most reliable, we would say either the 3.2 VR6 or 2.0TDI would be your best bet, although they are harder to find. We’re not saying the 1.8TFSI or 2.0TFSI engines are not reliable, but they do tend to have more problems at higher mileage. Any vehicle can be unreliable if proper maintenance isn’t followed. We’ve seen many TT MK2’s on the road that have hit 120,000 miles or more without any serious engine problems.
Here is an extremely useful guide on maintenance that should be followed to get the most out of an Audi MK2 TT. If you want to check out more Audi content, here is a write-up on The 6 Most Common Audi TT MK1 Engine Problems.