The 3 Most Common Audi B8 S4 Engine Problems

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No matter the level of maintenance you provide for a car, the engines will require some fixes or replacement, or both, at some point. The Audi B8 S4, just like other car engines you are familiar with, can come down with the following problems.

  1. Transmission Failure
  2. Water Pump/Cooling System Issues
  3. Carbon Build-Up

No doubt, the 13B new engine is one of the best engines out there, thanks to its competence and ability to withstand the test of time. Besides, it is an engine manufactured to provide ruggedness and longevity for its users if properly maintained.

More so, the Audi B8 S4 engine may provide users with everything they need, including comfort, strength, and reliability, but will at some point develop issues.

Every car engine ages and degrades over time. While the above issues are associated with the Audi B8 S4 engine, it may not be the same with other engines. Nevertheless, these problems don’t mean the Audi B8 engine is not the one to opt for.

Read along as I will be discussing the commonest problems of the Audi B8 S4 engine, including symptoms and what to do when these issues arise.

What Are The Most Common Audi B8 S4 Engine Issues?

1. Transmission Failure

Truth be told, the Audi B8 engine doesn’t have the exclusive monopoly of transmission problems. Most cars, if not properly maintained, are prone to face the debilitating effect of transmission issues.

Statistically, more than 20 per cent of the Audi B8 S4 engines released have developed the transmission problem. The percentage is high among older cars that run on this same engine.

The challenge is that the Audi B8 S4 engine’s mechatronics unit finds it difficult to regulate the oil system and causes another issue on the circuit board. At this point, it is easier to figure out why transmission doesn’t work as expected.

There is a reaction between the oil and board that leads to the production of heat which disturbs shifting gear, mostly when you try getting second gear from the first. Fortunately, you may not start to notice this issue until after covering about 220,000 miles.

Driving beyond this limit may lead to a bad driving experience on transmission. On the other hand, chances of not even getting close to this mile are high if you do not carry out the required maintenance.

However, before your engine will breakdown due to transmission failure, here are some symptoms you will notice.

What Causes Transmission Issues

Generally, three primary issues can trigger the transmission problem in a car engine, whether it is the latest models of the Audi B8 S4 or the older versions.

  • Torque Failure: For the engine transmission gears to achieve smooth shifting, it needs some pressure. However, the torque converter which is responsible for the supply of the pressure to the transmission fluid must be in good condition.
    Once it goes bad, the torque converter can’t perform its action of providing the needed pressure to the fluid. The torque converter often gets damaged due to worn-out needle bearings. The consequence is that the transmission will start to give off strange grinding noises as you drive along.
  • Clogged Filter: A clogged filter can also cause transmission to give issues to the engine. A clogged filter affects the condition and health of the transmission fluid. The fluid helps to maintain fluid pressure, cool the engine, and prevent oxidation. However, with a clogged filter, the fluid will become dirty and so causes sluggish shifting and transmission failure.
  • Low Or Leaking Transmission Fluid: The leaking of the transmission fluid reduces its level as well as the level of the pressure that gets to the transmission. If the driveshaft seal, pan gasket, or axle cracks, it causes the transmission to leak away.
    Once this happens, the engine will overheat and that can result in serious damage. The fluid can also be adulterated by contaminants that affect smooth gear shifting. At that point, the engine won’t achieve any transmission, either.

What To Watch Out For

Don’t just blow things out of proportion by assuming your engine is down due to transmission failure. You will notice these symptoms below:

  • Hesitation: A failed transmission of this engine will cause it to hesitate or outright refuse to shift to the proper gear. You may also notice a slow response while trying to shift from drive to park before proper engagement of the gear.
  • Shaking, Jerking, Or Grinding: Gear grinding is a common symptom of transmission failure. Since the problem begins with gear hesitation, it may later cause grinding as well.
  • Burning Smell: Leaking fluid isn’t a good sign for any engine, including 13B new Audi engines. If the burning smell from your engine is accompanied by transmission fluid, it indicates there’s a leak dropping on the heated part of the engine which results in burning.

What To Do

I recommend the replacement of a new impeller to solve the transmission issues in this engine. Although it sounds easier and simple, you may, however, encounter reliability problems if you opt for a plastic-made material.

Rotary engines’ pros and cons, as seen in Audi B8 engines, allow users to buy quality impellers like the original one as Audi does not produce custom spare parts. Fortunately, you may not encounter this problem again if you provide timely maintenance.

2. Water Pump/Cooling System Issues

Rotary engine pros and cons are many, with water pump failure-prone to issue as a con, which is common to Audi B8 S4 engines. Excessive water pump failure is one of the common engine problem. An impeller in this engine is responsible for pumping water via the water pump through the cooling system.

Unfortunately, Audi produced this component using plastic which is vulnerable to crack in a pressurized enviro6as engine becomes heated while working. Due to its location in the engine, it is susceptible to break or failure anytime.

Once there is a crack in the water pump and it begins to fail, it loses every pumping power and will only be able to pass little or no coolant through the cooling system.

It is quick to note the outcomes or symptoms of a broken or cracked water pump on 13B new engines, including the Audi B8 S4. I am sure you wouldn’t want to get stuck beside the road waiting for a towing truck. Why? Your engine could be overheating too much and could shut down its lifespan, if not careful.

What Causes Failing Water Pump

Water pump failure has been reported as a common phenomenon in Audi B8 S4 engines. But some issues are responsible for the failure. Much of the issues Audi model engine users have identified fall within the problem with internal seals and bearing of the engine.

The idea is that an Audi water pump can degrade, leading to a water failure. In addition, the Audi water pump impeller can also weaken as a result of it rubbing against the interior of the engine block.

When this happens, there will be debris, contaminants, and fragments forming on the system to affect the cooling system of the engine.

On the flip side, a bad seal can also be a major cause of water pump failure. By design, the seal is located between the water pump and engine block, the seal is responsible for keeping the coolant from leaking away. Additionally, the seal will help to prevent excess air from reaching the cooling system.

Once it damages, excess air will penetrate the cooling system and coolant will leak away, and the water pump becomes corroded.

What’s more, vibration in the drive pulley is another reason the water pump will not work efficiently and optimally. Here’s the thing: a loss of wobbling drive pulley will cause the bearings to wear down very fast and so cause the water pump to fail, resulting in some imbalance in the cooling system.

Another issue identified is a loose or worn-out tensioner belt. If the tensioner belt cracks, slips, wears, or becomes loose, the water pump will lack enough power to pump water for cooling.

What To Watch Out For

Now that we understand the responsibility of the water pump, let’s discuss a little about its synonyms when it begins to fail.

  • Excessive Engine Overheats: Overheating in engines is caused by a damaged water pump which leads to loss of fluid. When there is a shortage of water to cool the engine, the temperature begins to rise above normal.
  • Coolant Leaks: Coolants are secreted from the water pump using a series of seals and gaskets. A cracked, worn-out, or broken water pump will see these contents leak out.
  • Low Engine Coolant: A dying water pump will cause the coolant to leak, thereby resulting in a persistent drop in coolant level.

What To Do

I recommend a complete replacement of the water pump. However, it is best to go for OEM as you can cover about 50,000 to 80,000 miles with it. Alternatively, you may choose a metal impeller to curb water pump issues in the long run.

3. Carbon Build-Up

While carbon build-up is coming for all engines, it is pertinent to remind you that Audi B8 S4 engines are not left out. Fortunately, the carbon build-up is not something to worry about but it is worth mentioning among Audi B8 S4 engine issues.

Unlike the port-injection system known to inject fuel into intake valves, the Audi S4 works on a Direct Injection system that directly injects the fuel into the cylinders.

Engines that run on DI systems spray fuel directly into the cylinders, leaving the intake valves. As a result of this effect, intake valves build up carbon-gunk or sludge that pile up in the intake valve.

Although carbon build-up may be a threat to engine life, it will, however, impede the engine from being at its best. Carbon build-up will lead to the overall problematic performance of the engine because it will restrict the flow of air as well as reducing volumetric capacity.

What Causes Carbon Build-up

  • Low-Quality Gas/Fluid: Carbon build-up can result from low or incomplete combustion in the combustion chamber. It’s advisable to use the recommended gas and fluid. Switching from 5W-20 to 10W-30 will be a great remedy to stop poor combustion in the engine. When carbon builds, it can cause driveability issues.
  • Lack Of Or Improper Servicing: Maintenance is central to the health of your engine. The lack of it will cause a number of issues, including carbon build-up in the engine. Drivers and car owners must put service plans in place to prevent potential issues such as carbon deposit accumulation.
  • Excessive Stop-Start Travel: Experts have also identified stop-start travel during peak hours as largely responsible for carbon build-up in a car engine.
    When the engine carries much load, there is a higher chance that excessive carbon will accumulate. This is because congestion prevents the engine from regenerate, thereby causing carbon to build up.

What To Watch Out For

Let’s now take a look at the symptoms to watch out for since we already have an idea of what produces carbon build-up as one of the Audi engine problems.

  • Engine Misfires: The production of carbon build-up in this engine will cause it to misfire. You may experience things like rough idling.
    Engine misfire is a direct result of incomplete combustion in the cylinders. Specifically, when you start the car, it may start to stutter, hesitate, or the check engine light will start to blink ceaselessly.
  • Power Loss: When a car loses power, it should be a serious concern for any driver. This situation can be traced to a build-up of carbon deposits in the intake valve. The power loss symptom may start with overheating and stalling. You may also see excessive gas consumption and knocking sound.
  • Engine Knocking: Carbon deposit can build up on the intake valve or at the tip of the injector. When this happens, it can result in knocking sound from the engine.
    Since the accumulation of carbon is a consequence of a combustion process in the combustion chamber, the engine will cause a negative reaction by giving off a knocking sound.
  • Poor Performance: Carbon build-up will affect the engine’s overall performance. This may be accompanied by jerking or shaking. It is, however, difficult to notice this issue until you have covered a high mileage.

What To Do

Walnut Blasting is the solution I recommend for any carbon build-up problem. If you notice this issue persistently, I recommend you adopt walnut blasting every 50,000 miles you cover. Although there are other methods to solve the carbon build-up problem, the most effective, however, is to use walnut blasting.


1. How Long Does Audi Water Pump Last?

While manufacturers often put a cap on the life of many car components, including the water pump, mileage and age play an important role in determining how long they can last.

On average, the water pump of the Audi B8 S4 can last at least 100,000 miles. This doesn’t mean that you shouldn’t replace the water pump anytime it goes bad.

It is better to go for an original equipment water pump rather than the low-quality, less expensive replacement pumps that may not serve you beyond 20,000 miles.

2. What Is The Reliability Of The Audi B8 S4 Engine?

Overall, the Audi B8 S4 engine is a reliable engine that provides strength and ruggedness. Every engine tends to develop a fault as they age. Just as the name implies, the Audi B8 S4 engine is a B8 generation engine that uses a supercharged 3.0L V6.

However, no engine spends its lifetime without needing replacements of specific parts. The Audi B8 S4 engine is a reliable engine that can last for many years if you provide regular maintenance.

3. What Are The Specifications Of The Audi B8 S4 Engines?

Features: Specs:
Max Power (bhp@rpm) 328.5bhp@5500-6500rpm
Max Torque (nm@rpm) 440Nm@2900-5300rpm
Fuel System Direct Injection
Engine Displacement 2995 cm3
Position Of Cylinders V-Engine
Valvetrain DOHC

Final Thoughts

Audi B8 S4 engine is one of the best engines you can rely on. Considering the above-stated problems, it doesn’t imply that this engine is not the type to opt for. However, solving the above Audi B8 S4 engine problems requires you to be proactive.

You should avoid opting for after-market parts to replace any of the parts, including the water pump. Whether you are sure of the effectiveness or not, it can be a way to shut down your engine completely.

Usually, the best choice to make is choosing the OEM parts from Audi to replace any faulty or damaged parts. Ultimately, safety should be a priority.