Audi B8 A4
| |

The 5 Most Common Audi A4 B8 Problems

Chandler Stark

Meet Trey

Trey is an automotive enthusiast and has a huge passion for Volkswagen and Audi vehicles of all kinds. His enthusiasm started with the MK5 GTI, and he has massively expanded his knowledge over the years. When Trey is not delivering high-quality and in-depth content, we can usually find him working in his garage on his modified Genesis coupe. Trey created VW Tuning several years ago, and he is the primary visionary behind the content.

The B8 A4 was first introduced in 2008, as the successor to the B7 A4, and continued production through 2016. It came in multiple body types: sedan, avant/wagon, and allroad quattro (4-wheel drive), with an additional A4L model for the Chinese market. Essentially the A4L is a longer A4, that has a longer wheelbase and length, about 2.4 inches longer, than the standard A4. In 2012, the B8 received a facelift that redesigned various exterior and interior features like the headlights, taillights, fog lights, and updated exhaust.

The primary engines used were the 2.0L TFSI and 1.8L TFSI for the non-diesel versions, and the 2.0L TDI for the diesel vehicles. There were a few other engines, like the 3.0 TFSI, 3.2 FSI, 2.7 TDI, and 3.0 TDI, but they weren’t as popular. The 2.0 TFSI put out anywhere from 178-222hp and 236-258 lb-ft of torque. The 1.8 TFSI put out anywhere from 188-168hp and 170-236 lb-ft of torque. Lastly, the 2.0 TDI put out anywhere from 118-187hp and 214-295 lb-ft of torque. Overall, the Audi A4 B8 is a highly reliable vehicle. However, there are a number of common problems both engine and non-engine related in these vehicles.

Audi A4 B8 Common Problems

  • Water Pump Failure
  • Leaking Fuel Injectors / Failed Injectors
  • Excessive Oil Consumption
  • Faulty Power Steering Hose (causing speed wobble)
  • Carbon Buildup in Intake Valves

1. Audi A4 B8 Water Pump Failure

The water pump on this generation A4 is the most vulnerable and likely failure point on these cars. The Genuine Audi factory water pump was manufactured with plastic, instead of aluminum. Over time, as the water pump is subject to high heat levels in the engine bay, the plastic housing can develop cracks, resulting in coolant leaking and the pump failing.

Additionally, the gasket between the water pump and the thermostat is another failure point. Gaskets naturally wear down over time and become brittle, breaking and deteriorating easily. As this happens, the gasket becomes susceptible to leaks as well. The water pump has been known to fail up to 2 or 3 times prior to hitting 100,000 miles. This resulted in a class-action lawsuit in relation to A4’s made from 2009-2014 with the 2.0L TFSI engine.

Symptoms of a Failing Water Pump

  • Coolant leaks around the water pump and housing
  • Dripping coolant onto your garage floor
  • Fault code for coolant / low coolant light
  • Engine overheating (most tell-tale sign)
  • Rust, corrosion, and build-up along the water pump

Water Pump Replacement Options

For those with 2013-2016 A4 model years, Audi issued a recall, so you could be in luck for a replacement if you haven’t had the recall fixed yet.

For all other model years, you should replace your water pump with an aluminum water pump, instead of the OEM/Genuine hard plastic Audi water pump. The aluminum part will prevent any housing cracks and is significantly stronger and less likely to fail than the plastic parts. For those that are comfortable with DIYs, the repair is relatively easy, but will likely take 3-4 hours to complete.

Dealership/mechanic replacement cost: $600-$1,000 for the part plus labor
DIY replacement cost: $200-$250 plus 3-4 hours of work
Buy Here: Replacement A4 B8 2.0T Water Pump Kit

2. Leaking / Clogged Fuel Injectors

The A4 uses a direct injection system that uses fuel injectors to spray fuel directly into the engine cylinders. Over time, fuel injectors are prone to clogging, getting dirty, or leaking. The result of a bad fuel injector is not enough fuel being sprayed into the cylinders. Fortunately, it is not common for all of the injectors to go bad at once. These parts usually fail one at a time, but even one bad injector can cause significant performance and drivability problems.

When injectors fail, they can either get stuck open or stuck closed. This will cause either no fuel or too much fuel to be sprayed into the cylinder. This can happen consistently, or sporadically and will likely result in frequent misfires.

Symptoms of Bad Fuel Injectors

  • Starting issues – difficult to start, slow starting, etc.
  • Poor idling
  • Engine misfires
  • Engine fault codes (P0300, P0301, P0302, P0303, P0304)
  • Loss of power
  • Poor fuel mileage
  • Gas dripping out of the bottom of the engine

Diagnosing Bad Fuel Injectors

A lot of these symptoms can also be created by bad spark plugs, ignition coils, a bad water pump, etc. Because injectors aren’t cheap and difficult to replace, you’ll want to check the fuel pressure at the fuel rail before you go replacing any of the injectors.

Injector Kit: Replacement A4 B8 2.0T Fuel Injector Kit

Another possible issue that comes along with the P0300-P0306 fault codes is faulty ignition coils. Ignition coils turn a car battery’s lower voltage into the higher voltage needed by the spark plug to create a spark in the combustion chamber. If a single ignition coil is faulty, it will throw off engine misfires. If multiple ignition coils are bad, the car will have a tough time starting or not starting at all. We always advise replacing all the ignition coils when one goes bad to keep fresh ignition components at all times.

Buy Here: Audi A4 B8 2.0T OEM Ignition Coils
Buy Here:
Audi A4 B8 V6 3.2L OEM Ignition Coils

3. Audi A4 Excessive Oil Consumption

Many B8 A4 owners have reported their car consuming an above-normal amount of oil. This seems to be hit or miss for A4 owners, some report using 1 quart of oil every 1,000 or 2,000 miles, while some engines don’t have any issues at all.

In 2012, a class-action lawsuit was filed for 129,000 Audi’s for excessive fuel consumption. Audi initially determined that the problem was caused by an issue with the pistons and rings, but later found a fix with a new engine breather and a software upgrade. Along with the class-action lawsuit, Audi increased warranty coverage to 8yrs and 80,000 miles with an extended warranty of 1yr and 10,000 miles after the initial recall was fixed.

If you have excessive oil consumption, you can either continue to constantly re-fill the oil when it gets low, or take it in for the fix. Excessive consumption shouldn’t create any long-term reliability issues.

4. Audi A4 B8 Faulty Power Steering Hose / Speed Wobble

A4 owners have reported speed wobble or excessive vibration while driving at both low and high speeds. Audi determined that the problem was frequently caused by a faulty power steering hose, and is more prone with owners who tend to hard-brake frequently.

This problem is more common in early model year B8’s. Audi issues Technical Service Bulletin TSB2020332/4 along with a recall to have the power steering hose replaced to correct this issue. While the hose might need to be replaced, sometimes this issue can be fixed by flushing and replacing the power steering fluid. Additionally, a speed wobble problem could be caused by poorly balanced wheels.

Buy Here: Replacement A4 B8 Power Steering Supply Hose

5. Carbon Buildup in Intake Valves

Generally, all modern Audi engines use direct injection. Direct injection utilizes fuel injectors, one per cylinder, which spray fuel directly into the engine’s cylinders. In a non-direct injection engine, or one using port injection, the fuel is delivered through the intake valves, therefore there is a highly pressurized flow of fuel traveling through the valves, which keeps them clean and prevents gunk from building up.

Because the fuel is sprayed directly into the cylinders, there is no fuel going through the intake valves, and therefore, nothing to prevent the intake valves from getting gunked up from oil blow-back. The end result is a build-up of carbon deposits in the intake valve. As carbon deposits build up, airflow becomes restricted in the intake valve as it restricts the volume of air that can flow through it. This build-up and reduced airflow can result in:

Symptoms of Carbon Buildup

  • Decrease in performance / poor drivability
  • Rough idling, engine stuttering, etc.
  • Misfires

How to Clean Carbon Build-up in Audi’s

The most common and most effective way to reduce or clean carbon buildup in your Audi is through walnut blasting the intake valves. Walnut blasting takes crushed walnut pieces and blasts them through your intake valves with the use of compressed air. This process will blast away all of the carbon deposits and free up that extra space needed for maximum airflow.

Walnut blasting will require some special tools and takes approx. 4-6 hours. It’s not extremely easy even for an experienced DIY’er, so going to a mechanic is probably the best option. Audi dealerships typically charge ~$1,500 for the process, while you can find some indy shops that will do it for less than $1,000. We recommend walnut blasting your engine every 100,000 miles or so.

Audi A4 B8 Reliability

Despite the problems mentioned above, the A4 B8 can be a reliable car with the proper care and maintenance. Most of the common issues above have been addressed and recalled by Audi, however, the extended warranty on some of the problems like the water pump can be up for early model year B8’s. Overall, we’d probably score the car as “average” when it comes down to overall reliability, as problems become more likely and frequently as these cars continue to age.

If you happen to own an A4 B8, please let us know your experience with it in the comments below. This will help with our research and assist future readers in their decisions. If you want to read up on more Audi content, here is our write-up on the common problems with an Audi B9 S4.

How Reliable are 2008-2016 Audi A4’s?

The B8 generation of the A4 gets an average rating for reliability. The engines used in the B8 don’t suffer from any catastrophic engine problems but they are prone to a lot of ancillary systems failing such as the water pump and fuel injectors which can lead to expensive repairs.

What are the common problems with B8 versions of the Audi A4?

Common problems with B8 Audi A4’s ranging from 2008 to 2016 include: water pump failure, fuel injector failure, faulty power steering hoses, excessive oil consumption, and carbon buildup.

How long will B8 Audi A4’s last?

While this depends on an engine by engine basis the gas engines used in the A4 are typically decently reliable up until the 150,000 mile mark. Once an A4 surpasses those mileage levels they tend to get a bit more expensive to maintain. The 2.0 TDI diesel engine is capable of easily making it beyond the 300,000 mile mark.

Similar Posts


    1. Michael,

      Given that it is only at 80,000km, which is relatively low, as long as it has been maintained properly it should be safe. Make sure to get maintenance records prior to purchase to ensure maintenance intervals have been followed strictly. What motor does the one have that you’re looking at so we can give you more information.


      1. I´ve bought a model 2011, 87,000Km. Great conditions overall, all services done in time within Audi, it’s a 1.8T, I know have approximately two months with it, since I bought it i changed the oil, but after a month (roughly ~1,000km of ride) and the oil pressure was at minimum, I had to refill, as it seems, I went directly to the dealership at my home town and they told me to do once again, reset the odometer and drive for the 1,000km mark with the oil refill. If it does appear as low/minimum once again, to change the PCV Valve, or pistons/rings. I´ve also noticed it sometime has some dark smoke, it leaves a little trail near the trunk.

        What are your reccomendations due to mileage, oil consumption?

    2. Completely safe. Mine A4 is 2011/10 and just reached 340000km without any issues. All you need is to take care of it, and audi will make you happy 🙂

    1. Is it a Diesel engine type rattle at low rpms as usually as you’re getting going from a stop, especially on a slight inclination?

  1. I own a 2014 A4 with a 1.8l B8 CJEB 8K2… it only has 33,000km on it.

    It had the spark plugs changed in March 2018 along with the standard 4th year maintenance.

    The water pump went in 2022 and was changed along with the coolant tank as it had a slight crack.

    The car was working fine until last week when the engine started to sputter whilst I was going about 20km/hr, it went for about another 100m-150m and then it conked out & wouldn’t start-up again.

    The ECM is indicating that the high pressure fuel pump is faulting but when my mechanic went to check the spark plugs he found all 4 ignition coils fused to the spark plugs.

    He is concerned that the ECM may have been damaged due to this occurrence.

    Haven’t found any other cases online with a similar experience. Any idea what on earth could have caused this?

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.