If you want a stately sedan with plenty of power from the factory and massive potential for aftermarket improvements, the B8 or B8.5 S4 is perhaps one of the most well-rounded cars you can find. With its 3.0T supercharged V6, available manual transmission, four doors, sporty yet luxurious interior, and iconic Quattro AWD system, the B8/B8.5 S4 stands as a testament to Audi’s prowess in creating a car that truly does it all. It’s big enough for road trips, nimble enough for the track, and sporty enough that you can’t help but smile every time you press the throttle on a b-road, highway, or back straight. With the earliest B8s becoming increasingly affordable, even in pristine condition, and the B8.5 quickly reaching similar levels of affordability thanks to the release of the B9, these cars are quickly gaining popularity as platforms for easy, accessible, and relatively cost-effective performance. However, if you intend to scoop one for yourself, you should know what to expect on the front end so you can prepare for potential repairs. These are the common issues we’ve found with the Audi B8/B8.5 S4 and how you can address them with some help from the best source for European parts and accessories anywhere.
It’s not just for BMWs. The early model B8 S4 had two inherent weaknesses that were corrected under recall. Both the Water Pump and the Thermostat for 09-10 model B8 S4s were subject to multiple recalls due to failures. The Water Pump housing originally was plastic but was revised with a metal housing version. Check under the supercharger for a visual inspection if you are looking at a B8 produced before 2010. The thermostat is harder to visually inspect, as it is inside the thermostat housing. You should check the service records to see if the recall has been performed. For a safe bet, you can replace it yourself as well as perform the cooling system refresh with our Assembled by ECS Cooling System Refresh kit.
According to some owners, the sunroof deflector creates noise with the windows down that has been described as less than comfortable. Your sunroof may or may not have had this replaced. The correct part number for the updated version is 8D9-877-651-A.
Power Steering Wandering:
In B8.5 S4s, which had electromagnetic steering systems, owners report steering wandering. This is the result of software issues and can only be fixed by a dealership software update. However, the fix has yet to be found and dealerships will notify affected owners once it becomes available. For now, there isn’t much owners can do that is approved by Audi.
6spd Clutch Noise:
In manual transmission models, owners have experienced ‘creaking’ noises from the clutch during operation. There have been multiple updates to technical service bulletins but no permanent solution has come from Audi. If you are worried about excessive clutch noise and are planning to upgrade your S4, it might be in your best interest to upgrade your clutch system with one of our performance kits. If you want to learn more about our lightweight flywheel option and clutch upgrades, our article explaining how they improve your B8 is a great place to begin.
Some owners have experienced ‘brake noise’ from the factory brakes. There is an updated parts list from Audi, which solves the noise issue, but we always look for an improvement, not just a replacement. If you are concerned with brake noise and are planning to add more power, it is probably a good idea to make the switch to more aggressive brake options. Our list of brake upgrades will have what you need, be it a service kit or an upgraded performance brake kit.
These are some of the most common issues associated with the B8/B8.5 S4. With a bit of knowledge on the front end, you can make a wise purchase decision and know what to expect. Since this list is fairly short and nothing is excessively dangerous or worrisome, you can expect a solid ownership experience. These are excellent vehicles full of tons of potential. For a good source of upgrades and modifications, check out some of our articles on how to improve your B8 S4 for power and performance as well as handling upgrades and more.