2018 Audi S5

An Audi dealer has just diagnosed my 2018 S5 Cabriolet Prestige with vacuum system contamination caused by water pump failure. I had requested the diagnostic due to small coolant leaks on the engine and loss of coolant in the expansion tank. No warning lights and no overheating yet. Not yet aware of any loss of performance. I have been advised it is unsafe to continue driving the car. Dealer has quoted me $7800 estimate to repair the car. Purchased the car in 2021 as a Certified Pre Owned vehicle, and it now has about 84K miles on the OD.

VEHICLE Year: 2018 Make: Audi Model: S5 Prestige Trim: 3.0 TFSI (EA839 V6 Turbo) Mileage: 86,000 Engine Code: CWGD COMPLAINT TITLE Latent Engine Failure – EA839 Piston Skirt + Rocker Arm Defects – Dealer Broke Engine Cover, Left Wiring Harness Dangling – Audi Denies Despite Having DIY Receipts For Maintenance DESCRIPTION At 86,000 miles, my 2018 Audi S5 Prestige suffered internal engine failure from metal debris and cylinder wall scoring. Dealer borescope showed: Metal in oil filter (bearing + non-ferrous “other metal”) Deep scoring on multiple cylinders No check engine light. No power loss yet. Still drivable — but seizure is imminent. DEALER NEGLIGENCE AT [Audi Of Chantilly] (Penske Automotive Group): Engine cover broken — not reported Wiring harness retainers/harness clips left undone on both sides after spark plug removal → Improper reassembly risks damage to harness and engine/components — safety hazard. This matches TWO known EA839 defects: Piston Skirt Cracking – Sept 2025 Warranty Extension covers identical symptoms (debris + scoring). Denied only for 6,000 miles over 80k cap. Pre-06/2018 Rocker Arm Needle Bearing Failure – Audi revised mid-2018 (PN 06M109417H → 0P2109417, double bearing size) because originals shed metal. Garage Auto Sports: “Known to fail… Audi fixed it.” Link AudiWorld: 200+ cases Link AoA DENIAL – FALSE “Over mileage” → Rocker defect has no cap “Undocumented maintenance” LIE → All oil changes DIY with Audi 508.00 oil + OEM filters → Amazon invoices attached → Never asked for proof $32,000 quote. 100% denial. SAFETY RISK Sudden seizure at speed No warning Dealer damage worsens risk REQUESTED ACTION Investigate EA839 2017–2018 for piston + rocker failures Recall / extend warranty for pre-06/2018 builds Probe denials without proof request + dealer negligence ATTACHMENTS Denial letter Dealer Diagnostic 32k Quote Borescope report Amazon receipts Broken cover + undone retainers photos Screenshots (links above)

To Whom It May Concern, I am submitting this complaint to report a mechanical issue with my 2018 Audi S5 Sportback. Around 57,000 miles, the engine began making a noticeable ticking noise, which I have been advised is due to failing rocker arms. This issue has raised serious concerns, as it can lead to engine misfires, reduced performance, and potentially catastrophic engine damage if left unresolved. The problem appeared without warning, despite regular maintenance and no prior engine alerts. I believe this may be a defect affecting other Audi models with similar engines, and I urge the NHTSA to investigate whether a recall or technical service bulletin should be issued. Vehicle Information: Make: Audi Model: S5 Sportback Year: 2018

While driving, my Audi overheated randomly, started smoking, had to be towed. Had 72,800 miles, was serviced by Audi at 70k miles and all prior recommended services. Towed to Audi dealership, quoted 29k in engine repairs, Audi could never tell me why engine overheated. Would not cover any expense because “i didn’t buy it there”. Insurance denied two claims because Audi reported it as engine failure although they couldn’t prove what happened to cause the heating, said it was one of the worst engine overheating they had seen. Prior to overheating, service driver system popped up for the first time. Temperature gauges were normal. Will not start or run since. No accountability taken by Audi at all, even through corporate. I believe my safety was at risk because the engine would have caught on fire had I not of noticed or pulled over. A Good Samaritan even pulled behind me to check on me because they saw it smoking in passing. I have a video of Audi inspection. Date is estimate of event, I would have to research. Vehicle was purchased by prior owner as cpo from Audi at 30k miles and serviced since at same Audi dealer every recommended service and prior if issue arose, I have all service records.

After driving for 7 to 8 minutes less that 45 mph, a yellow warning lamp and an audible warning indicating unsafe coolant temperature displayed on the dash. An overheating engine is unsafe for me and drivers near me. I immediately pulled over and turned off the A/C. I then turned on the heater, and after 15 minutes slowly drove 5 minutes to a repair shop (Import Autohaus, Hull Street). The repair shop diagnosed a defective water pump. The pump has not been inspected by anyone other than the mechanics at the repair shop.

I received a coolant overheating message, pulled to side of road. Let vehicle cool off although it just showed coolant warning and actual engine temperature showed normal along with oil temperature. Started car back up and it was ok, drove about a mile, engine started steaming, white smoke out of exhaust, system failure had to pull off and be towed. Engine is destroyed at 72,833 miles.

I was returning home from visiting family. My drive was approx 140 miles home. The car was running/driving normally when I stopped at a gas station to get a snack. When I came back to my car and attempted to start it, it would not start and had camshaft and crankshaft sensor DTC's. I had to tow the car to my repair shop who determined that the issue was the rocker arms. Despite performing regular maintenance above and beyond what the manufacturer recommends, two rocker arms fell apart inside the engine (needle bearings came out) and sent metal through the engine, causing it to need to be replaced. It was later determined that this was a known issue by Audi, and that they redesigned the rocker arms at a later date. The did not issue a recall or any extended warranty for the effected models. This cost me $16,349 out of pocket to repair. I contacted Audi several times and they refused to rectify the issue. I have came across several others who have experienced the same issue. I have supporting documentation as well as part numbers and dates that I can provide upon request. This type of issue is a saftey concern because this can leave a driver stranded. When this issue happend I was over 75 miles away from home. Luckily I was able to find a tow truck and had the funds to cover the expense of having the car towed back to my home town. However, this issue could leave someone stranded in the middle of nowhere if they werent as lucky as I was.

The 2018 year for the Audi S5 has a notorious rocker arm failure within the engine. Audi is aware of this problem because they have revised the part for later build dates. However, they have failed to remedy the issue for the vehicles that fall within the problematic build dates. Once this failure occurs, it is catastrophic and will require a new engine.

MAXIMUM OIL LIGHT WARNING LIGHT, REDUCE OIL LEVEL, SINCE PURCHASED. GASOLINE GETTING INTO OIL. REMOVED 9 QUARTS OF GASOLINE SATURATED OIL OUT OF CAR. AUDI SAYS I NEED TO DRIVE CAR MORE. AUDI RECENTLY REPLACED OIL & FILTER AND SAID TO MONITOR . DROVE CAR FROM DEALERSHIP SERVICE, WARNING LIGHT CAME BACK ON, CHECKED ENGINE WITH AFTER MARKET OIL DIP STICK, STONE SMELL OF GAS IN OIL. VEHICLE TOWED BACK TO DEALERSHIP