The S5 is the high performance variant of the A5 coupe and sits just below the more extreme RS 5 in Audi’s model lineup.
Its more powerful engine makes it a better grand tourer than the A5, but it’s still more practical as a daily driver than the RS 5.
In this article, we’ll take a deep dive into the S5’s common issue and their solutions.
Table of Contents
1. Carbon Buildup
The 4.2 V8 FSI engine found in early models of the Audi S5 is notorious for its excessive carbon buildup issues which can affect its performance after 60,000 miles.
These engines used early versions of direct injection which sprayed fuel directly into the combustion chamber.
Since fuel wasn’t reaching the back of the intake valves to regularly clean them out, carbon deposits will accumulate after a couple of years of driving.
The V8 was offered in the coupe models of the S5 from 2008 to 2012.
The supercharged 3.0-liter V6 that replaced the V8 from 2013 to 2017, and was also equipped in early models of the S5 convertible since 2010, can also suffer from excess carbon buildup, but symptoms would usually only appear at higher mileages.
Common symptoms of excess carbon buildup include:
- Poor fuel economy
- Shaking or vibration at higher RPM
- Limp mode
- Check engine light
Here’s how owners on A5OC.com described their issues;
“I have the dreaded carbon buildup in my 2009 S5 4.2 V8 only has 35k miles on it. Pulled the codes and got the p2006 and p2007 error. Dealer confirmed this and also that the engine has been running rough and the CEL was due to the carbon build up.”
“I just had mine done as well, under warranty (28k miles) I had cold engine misfires, and they tried numerous things before they finally said ‘We think carbon build up may be preventing one of the intake valves from not opening properly on start-up, so we’re going to take the cover off and do a cleaning.’ That took care of it and the car feels like it did when it had 28 miles.”
Another owner on AudiWorld.com had this to say:
“2010 S5 74k. Well engine light started blinking. Took it to Audi and suggested the carbon flush by BG, did it and a month later engine light blinking again. This time i knew what was wrong. On the gas it started to shutter almost misfiring. So i figured it had to be the injectors possibly clogged cause i had just replaced the coilpacks and spark plugs myself. Dealer stated yup and that it was under warranty due to the fact BG did the carbon flush. so they replced the injectors and found a ton of carbon on the back of the intake valves. Some of the valves had almost 5 mm of carbon built up.”
The best way to clean out the carbon deposits is to have the intake valves professionally walnut blasted.
This can cost around $500 at an independent Audi or Euro specialist, and most enthusiasts recommend getting it done every 60,000 to 100,000 miles.
If you want to go the DIY route, you can also remove the intake manifold and carefully scrape off the carbon buildup manually after spraying it with solvent to soften it up a bit.
Using premium gas and driving the car spiritedly so the engine can reach popper operating temperatures can help reduce the carbon buildup, but it doesn’t completely eliminate the issue.
2. Coolant Leaks
Coolant leaks due to cracked water pumps and thermostat housings are a very common problem on all model years of the Audi S5.
The water pump and thermostat housing, as well as a lot of pipes and fittings, are made out of plastic which gets brittle and cracks over time.
Common symptoms of coolant leaks include:
- Low coolant warning
- Empty coolant reservoir
- Visible coolant leaks
- Smell of burnt coolant
- Overheating issues
- Heater doesn’t work
The thermostat of the V8 engine also has a tendency to break and get stuck which causes the car to overheat if the car doesn’t have any coolant leaks.
Here’s how owners on Audizine.com described their experience:
“2012 S5 suddenly overheated for first time ever – stop engine light and check coolant level message. Pulled over, coolant leaking etc. Towed to the local Audi service shop (who I like actually, pricey of course but they have always done good work). They pressure tested the coolant system for 24 hours w 0 leaking so diagnosed as a bad thermostat and possibly water pump.”
“I had an overheating situation yesterday with my 2013 S5 while driving on the highway away from home. Luckily I found a local dealership 4 miles away and was able to limp there (stopping frequently to allow the engine to cool down). They found codes for a problem with the thermostat and are recommending that they replace it, along with the water pump… The total bill is estimated to be around $1900.”
“I have 2012 S5 as well and had the same problem a year or so ago at 40K miles and it was the thermostat. They seem to crap out at around 40-45K from what I’ve heard.”
“I had the thermostat replaced on my V8 S5, RS4 and my wife’s V8 S4 during ownership of those cars. All displayed the same temp needle behavior you described. That V8 is scorching hot and they are known to eat thermos over time. Eventually you get a message telling you the engine is too hot and to stop driving. This was covered under warranty for the RS4 and my wife’s S4, but my S5 had 55k on it and I paid out of pocket.”
Although Audi and Volkswagen have already revised the thermostat housing a few times, it continues to be a common issue — especially in vehicles that are a few years old.
If you need to have the repair done out of warranty, a water pump and thermostat assembly costs around $400.
Installing a new water pump and thermostat is a little more difficult in the B8.5 models with the 3.0-liter V6 is a little harder because the supercharger has to be removed to get to the water pump.
Getting it fixed at an Audi dealer can easily cost you over $1,000, but a VW or Audi specialist should be able to do the job for a much lower price.
For the B9 S5 from 2018 onwards, the front bumper has to be removed to access the water pump assembly.
3. PCV Issues
The PCV valve or air oil separator is a common point of failure in different model years of the S5 even before the car reaches the 100,000-mile mark.
The PCV (Positive Crankcase Ventilation) is an emissions control system that recirculates blowby gasses that are harmful to the environment back into the engine so that it burns up cleaner.
A broken PCV valve can affect the air-fuel mixture and also create excess pressure to build up in the crankcase, which causes the seals and gaskets to wear out quickly.
The PCV valve is also made out of plastic, which cracks over time and causes coolant to mix with oil.
Common symptoms of a faulty PCV valve include:
- Rough idle
- Hissing or whistling noises
- Coolant mixing with oil
- Low coolant level
- Rear main seal leak
- Excessive oil consumption
- Oil cap is hard to take off due to too much suction
Here’s what one S5 owner on A5OC.com had to say:
“2014 S5 – 61837 miles. I’ve got the PCV fault and suction issue when trying to remove the oil cap when the engine is running. It’s also running rough on idle.”
The 2017 to 2019 model years of the S5 also had issues where the PCV breather hose failed prematurely.
One owner on Audizine.com also shared their experience:
“2018 B9 S5 SB PCV Failure. While driving home last night in the cold, my car started bogging during deceleration when coming to a stop. I quickly parked it and noticed it had a wandering/hunting idle bouncing between 1k and 2.5k. I also noticed a loud whistling sound from under the hood. When I placed my hand over the oil-cap I could feel suction; while attempting to remove the oil-cap I could also feel immense suction. All of this points to the PCV unit failing, introducing a rather large vacuum leak, forcing the motor to run lean and then hunt based on lambda sensor readings.”
To address the premature failures in the 2017 to 2019 models, Audi updated the breather line with an improved membrane/diaphragm.
A new PCV valve and other associated parts typically cost around $100 to $200.
It’s a pretty simple repair on the 4.2 V8, but with the 3.0-liter V6 models, the supercharger or turbocharger has to be removed to access the PCV system, which can easily bump the total repair price to over $1,000.
A lot of B8 and B8.5 S5 owners replace the PCV and water pump at the same time to save on future repair costs since both components are known to have issues and can be easily removed once the supercharger is out.
4. Timing Chain Issues
Older models of the Audi S5 with the supercharged 3.0-liter V6 have a tendency to rattle on startup due to issues with the timing chain tensioner.
The rattle is usually only heard after a cold start and only lasts for 1 to 3 seconds.
This problem typically affects the 2011 to 2014 model years of the S5.
Although similar rattles often mean that the timing chain is stretched or that the guides and tensioners are very worn out, actual reports of timing chain failures are quite rare.
If the rattle is persistent and lasts long after the engine is first started, you might have a bigger timing chain issue.
Although the 4.2 V8 had a history of timing chain failures in the Audi S4, the S5’s 4.2 V8 FSI engine has a different design and doesn’t suffer from the same issues.
Common symptoms of a stretched timing chain include:
- Engine rattle
- Rough idle
- Hard starting
- Engine stall
- Reduced engine power
- Check engine light
- Timing related trouble codes
Here’s what a few owners on AudiWorld.com had to say about their timing chain problems:
“I have a 2015 S5 with only 43k miles. Yesterday the car idled rough and I heard a rattling noise for several seconds under the hood, driver side. Noise stopped after a minute or less Got it to the shop and they say it’s the driver bank timing chain tensioner. Recommended I change both sides. I think this is going to cost about $2,500 at my indy shop.”
“I had this rattle develop on my 2015 S5 at about 40k miles. Was verified by my dealer and upper timing chain tensioners were replaced under warranty. Was not an engine out procedure. Heads were not removed either, however, down pipes and converters were.”
Another S5 owner on A5OC.com had this to say:
“My 2013 S5 3.0 t is noisy at start and it is the chain tensioner on the driver side per TSB 2039995/1. I brought the car to Audi to get a quote and of course the TSB is not covered as the car is outside the warranty. Their initial quote was $9300 but after verification I realized they were changing all the chain drive but not the tensioner. I told them something was wrong and they revise the quote which went down to $4800 after they realized their mistake.”
Audi released a TSB (Technical Service Bulletin) for all models equipped with the V6 3.0 TFSI engine that recommends replacing the old timing chain tensioner with an updated part to get rid of the rattle.
The TSB also states that the rattle shouldn’t lead to any other issues, but this doesn’t guarantee anything especially if the car has really high mileage or hasn’t been properly taken care of.
Replacing the timing chain and tensioner is an engine out repair and can easily cost over $5,000 if done at the dealer. You can probably save 50% or more if you take it to an independent Audi or Volkswagen specialist.
5. Crank Pulley Failure
The crankshaft pulley of the Audi S5’s 3.0-liter supercharged V6 has a tendency to break apart and separate, which damages the serpentine belt and other accessories in the front of the engine.
When the crank pulley fails and the serpentine belt breaks, the supercharger won’t provide any boost and the power steering will also stop working.
This issue is more common on the early models from 2010 to 2013, but it can also affect newer cars with an updated pulley.
The B8 and 8.5 Audi S4 also have lots of reports of crank pulley failures.
One owner with a 2013 S5 described their experience on Audizine.com:
“B8.5 crank pulley failure at 57k. Basically the crank pulley failed which slid both belts forward. The sc belt caught the acc belt and slid it up the sc pulley. Then the sc belt flew off and the acc belt began to partially wrap itself (about 2 ribs of the belt) around the sc pulley while still running the accessories. Eventually it snapped.”
A new crankshaft pulley from Audi costs around $500 but aftermarket replacements are much cheaper at around $200.
Some owners replace the factory pulley which has a 2-piece design with aftermarket parts that are more durable.
Aside from replacing the pulley itself, you’ll also have to replace the serpentine belt and any other parts that were damaged.
Replacing the pulley and any other necessary parts will usually take an independent Audi specialist around 2 hours if no other major parts are damaged.
6. Rocker Arm Failure
Early model years of the B9 Audi S5 from 2018 to 2019 can suffer from rocker arm failures that can lead to severe engine damage.
This issue has only affected a small number of cars so far, but it can be very expensive to fix.
One common symptom of bad rocker arms is a loud ticking sound, which is much louder than the normal ticking sounds from the injectors or the high pressure fuel pump.
If you continue to drive the car, the rocker arms can wear out and send metal shavings into the rest of the engine.
One S5 owner described their experience on AudiWorld.com:
“My beloved 2018 S5 went into the Audi Dealer… The car was idling rough and a little louder than usual at idle. The typical ticking noise and also the exhaust was just a little rougher sounding than I was used to hearing… The car itself drove fine and I noticed no performance issues, other than something sounded ‘off’.”
“Well they called me back and said, bad news… We found metal shavings in your oil. The car went in with 52,xxx on the odo. I had just had the 50k maintenance under audi care performed there 6 weeks or so before that. The 40k also. I had bought the car with 32K CPO. The good news is my warranty covers it. I figured a couple weeks and good as new. That was 9 weeks ago.”
“They suggested both sets of 12 roller rockers (24 total) would need to be replaced and they ordered them. The parts took awhile to come in, and they did find damage to 1 of the existing roller rockers that they believe was the source of the metal shavings.”
Getting the rocker arms replaced at the dealer can cost $10,000 or more since the cylinder head has to be torn apart and rebuilt.
All the parts required for the repair costs around $1,500. An independent Audi specialist might only charge around $5,000 or even less to replace the rocker arms.
If the rocker arm failure damages the engine and you’re out of warranty, it’s probably best to look for a used engine to swap in.
It’s also important to note that many Audi enthusiasts consider the rocker arm problem as overblown since only a very small percentage of cars out of the several thousand that Audi has sold has suffered from failures.
7. Dual-Clutch Transmission Issues
The 7-speed S-tronic dual clutch transmission, also known as DSG (Direct Shift Gearbox), found in early models of the S5 convertible have a tendency to fail due to mechatronic issues.
The mechatronic unit is the electro-mechanical part that controls the shifting of the semi-automatic dual-clutch gearbox.
Common symptoms of a faulty mechatronic unit include:
- Rough/hard shifting
- Jerky acceleration at low speed
- Won’t shift into reverse
- Won’t shift into certain gears
- Shifts into neutral
- Hesitation to accelerate
Mechatronic failures are more common in the 2010 to 2012 model years of the S5 convertible, but early 2013 models of both the coupe and convertible can also suffer from similar issues.
Early S5 couples with the V8 engine came with a traditional automatic, so they aren’t affected by these DSG problems.
The S-tronic was only paired with the V6 models of the first generation Audi S5.
The 2013 and newer model years of the higher powered RS 5 can also suffer from DSG failures.
One S5 owner described their experience on AudiWorld.com:
“I am having issues with my 2011 Audi S5 DSG 7 spd transmission MSE Code transmission. I am getting the dreaded “gearbox malfunction” code, as well as the “TPMS” light code that comes on shortly before or after the gearbox malfunction code.”
‘I have hard shifts, sometimes no reverse, my car will go into limp mode with the top speed being 50mph. If I have to drive slow or in stop and go traffic the codes will come on, however If i can turn the car off and restart the car i can get reverse gear.”
Another owner also had similar issues:
“I am suffering from a similar issue with my 2011 S5 3.0 cabriolet. Rough shifts, TPMS sensor comes on, then lost Reverse gear and also Drive sometimes. Dashboard warning messages about the transmission. Restarting the car gets me home.”
“My scan tool pulls this error: Valve 3 in Transmission Part 2 P17D5 00  – Mechanical Malfunction”
“The mechatronics were replaced by Audi 4,000 miles ago with little improvement. They now want to replace the whole transmission for more than the car is worth.”
The S-tronic transmission has to be serviced with new fluid every 40,000 miles if you want to avoid premature failures.
That said, the mechatronic unit in the pre-facelift B8 cars can still eventually fail even if they were properly maintained.
If the transmission is already having problems, a fluid and filter change might be able to get rid of the issues.
The DSG is also very sensitive to under or over filling of fluid, and can run into problems if it isn’t serviced correctly.
There are also mechatronic repair kits that cost around $800 that can sometimes fix the gearbox issues.
Replacing the entire mechatronic unit can cost around $2,000 to $3,000. If you need a new transmission, it can easily cost you over $5,000.
8. Suspension Issues
The Audi S5’s suspension has a tendency to wear out even at relatively lower mileages.
The worn ball joints and torn control arm bushings will eventually cause noticeable problems with the suspension.
Common symptoms of worn suspension components include:
- Creaking or clicking sounds
- Uneven tire wear
- Vibrations in steering wheel
- Handling issues
- Alignment problems
Here’s how a few owners described their experience on AudiWorld.com:
“I recently had a front brake job on my 2014 S5 with 40k miles at a non Audi repair shop. The mechanic told me all 4 upper control bushings were worn and needed replacement.”
“It’s an 09 S5 V8, with about 39k kms on the clock. I took it for a car inspection today and the results were that theres cracking in the bushings on all the front control arms, top and bottom.”
“Mine lasted 40k, replaced earlier this year – also 2018 (don’t drive it that much). For rubber, it’s just as much about the age as it is the mileage – but yeah, seems to be another Audi “thing”. Unfortunately, Audi doesn’t sell just the bushings, you replace the whole arm.”
New control arms from Audi are quite expensive and cost between $300 to $500 a piece. Getting them replaced at the dealer can easily cost over $1,000 because it will also require a few hours of labor.
Aftermarket replacements are cheaper with complete kits costing around $500 to $700.
You can also just replace the bushings which only cost a few dollars, but it will take some effort to remove the old ones and you’ll need a hydraulic press to install the new bushings.
If you replace the entire control arm, you’ll also fix any issues with the ball joints.
9. Sunroof Issues
A number of second generation Audi A5 owners have had issues with squeaks and rattles coming from the sunroof.
These noises tend to appear when driving on uneven roads and up driveway ramps which cause the chassis to flex and allow parts to rub against each other.
Here’s how a few owners described their experience on AudiWorld.com:
“I had the same issue in my 2018 S5 coupe. Creaking noise like hard plastic rubbing on hard plastic from the rear of the moonroof spanning the entire width of the car. It took THREE trips to the dealership to get it mostly fixed. First two times they added padded felt material inside and the third time they bought a new trim piece for inside it and lined it with more felt. It’s now much quieter than before. Used to make noise all the time when driving and any road camber or surface change would make it noisy.”
“I have an annoying rattle from the sunroof when open, either on tilt or fully open! I had my original S5 replaced by Audi after an initial 8 months of faults including the sunroof. My new car arrived on 1st March 2018 and has developed the same sunroof rattle.”
“I dropped off my B9 S5 at Audi Central Houston because the creaking and moaning sound is driving me nuts. It is very prominent and near constant on the terrible roads in and around Houston. I can reproduce the creak by simply pushing the headliner a bit around the sunroof on the driver’s side.”
Over time the additional stress caused by the flexing of the chassis can also cause parts like the sunroof frame to crack.
A new sunroof frame costs around $1,000 if you need to get it replaced out of warranty.
You might also have to get creative and apply lubricant or stick some foam in between the offending parts to dampen the noise that they’re making.
10. Window Issues
The Audi S5’s window motors tend to have shorter lifespans because they constantly have to roll the windows up and down whenever the doors are opened.
The windows open slightly when you pull the door handle to make closing the doors easier without having to worry about the air pressure inside the cabin.
The glass then rolls back up when the doors are closed which allows it to rest nicely on the rubber seals.
This constant operation will eventually burn out the window motors/regulators.
Here’s how owners on AudiWorld.com described their experience:
“2018 Audi S5 Window Issue. I’ve noticed an issue with the window rolling down when I try to close it.”
“Mine took 4 trips into the dealer. Wasn’t finally resolved until they replaced the window control unit. Even now, every once in a while it doesn’t fully roll up when I shut the door and I get some wind noise, etc. until I manually do it.”
“My S5 coupe power windows have always intermittently been flaky; however, as of Monday this new issue cropped up and is consistent. The windows automatically drop down about 1 cm to clear the sill for operation (open/close). What is happening this week is that the driver’s side only window will drop several inches when I open either door. When I get into the driver’s side seat and close the door, it will then only rise back up the 1 cm leaving the several inches open still.”
A new window motor is quite expensive at around $400. Aftermarket replacements are much cheaper and can range from just over $50 to $200 a piece.
The window issue could also be caused by a faulty door control module, a busted fuse, or some other electrical wiring issue.
In a lot of cases, the windows might just need to be reset by opening the windows fully then holding down the window button for 10 seconds, then closing them back up again then holding down the window button for another 10 seconds.
11. Speaker Issues
A number of second generation S5 owners have complained about the quality of the sound system.
Complaints are more common in the 4-door Sportback model from 2018 onwards, which many feel doesn’t have any bass output.
It’s also apparent on the regular A5, as well as the RS 5 models of the Sportback.
Here’s how one owner described their experience on Audizine.com
“The day I got my ’20 S5 sportback with B&O, I told myself how underwhelming the audio sounded. Specifically the lack of bass/punch to the music.”
Several owners eventually discovered that the subwoofer in the back was wired the wrong way and was working out of phase which led to thin sounding bass.
To correct the issue, one has to simply switch around the two subwoofer wires and solder them back on.
Many owners have also complained about the door and center speakers rattling which could be caused by loose fasteners or inadequate sound dampening.
Some were only able to get rid of the rattling by replacing the factory speakers with higher quality aftermarket ones.
Audi S5 Pros & Cons
- Stylish exterior
- Upscale cabin
- Quick acceleration
- Confident handling
- Comfortable ride
- All-wheel drive
- Modern tech and creature comforts
- Expensive parts and maintenance
- Limited interior storage
- Rivals have more performance
What Do The Reviews Say?
“The S5 is very balanced for both performance and luxury. It’s a beautiful vehicle inside and out and has easy-to-use controls. It’s genuinely enjoyable if you want to take it on twisty roads, and it doesn’t sacrifice comfort and luxury.”
“We tested an S5 Sportback, which is the four-door hatchback. There’s plenty of power from the turbocharged V6 even if it’s not immediately explosive off the line. Once on the move, acceleration is swift, steady and satisfying.”
“The S5 is capable around corners too. Our car came equipped with the optional S Sport package. It helps blend the best of all-wheel-drive traction with the nimble feeling of a rear-wheel-drive car. The S5’s dynamic steering also feels well matched to whatever drive mode setting you’re in.”
“We continue to be amazed at the balance of the S5 Sportback. Comfort is just as much a priority as performance. The front seats are very supportive and pleasant, and the available heated and ventilated elements work swiftly.”
“Getting in and out of the S5 Sportback’s front seats is easy. If you’re on the taller side, you might have to duck to get into the rear seats due to the sloping roofline. There’s a good amount of room for front occupants plus plenty of adjustment range for the driver. The rear seats are decent in terms of comfort and space for two adults up to about 5-foot-10 or so.”
What’s the Resale Value of an Audi S5?
Here’s a quick look at used car pricing for the Audi S5 on Edmunds at the time of writing.