According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2018 Audi S8 has 1 documented issue. No issues are rated critical, indicating generally reliable ownership. DIY maintenance guides at au7o.io.
On the 2013-2018 Audi S8 4.0T TFSI V8, audi TSB 2046724/5 covers sporadic warm-engine no-start or long cranking after the vehicle sits without fully cooling. A rich-mixture DTC may occur, but often there is no DTC. Audi’s procedure distinguishes fuel in the oil from a short-trip profile, ECM software, high-pressure injector leakage and high-pressure fuel-pump leakage rather than assuming one failed component.
Common Symptoms
Warm-soak no-start with normal starter operation
Long cranking followed by rough running for a few seconds
How to Fix
Have the dealer read DTCs and ODIS fuel-in-oil value, verify ECM software and perform Audi’s high- and low-pressure holding tests. If high-pressure behavior is abnormal, borescope the combustion chamber to identify a leaking injector. If low-side pressure builds correctly but drops more than 1.5 bar in the first 15 minutes, Audi says at least one HPFP may be leaking and directs replacement of both pumps plus an oil change. Select no pump or injector until the test identifies the path.
Owner tips & cautions
TipRecord engine temperature and how long the car sat before the hard start; do not approve pumps or injectors without the pressure-hold results.
FUEL SYSTEM, GASOLINE:DELIVERY:HOSES, LINES/PIPING, AND FITTINGS
Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2013-2016 Audi A8 and S8 vehicles. The fuel supply line for the high pressure fuel pump may become porous and leak fuel.
Campaign #19V05700028/01/2019
STRUCTURE:BODY:HOOD
Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2013-2018 Audi S8 and A8 vehicles. The seal around the engine compartment may come loose and contact hot engine components.
Campaign #20V39700007/07/2020
ENGINE AND ENGINE COOLING:ENGINE:GASOLINE:TURBO/SUPERCHARGER
Volkswagen Group of America, Inc. (Audi) is recalling certain 2013-2017 A8, S6 Sedan, S7, S8, and 2014-2017 RS7 vehicles. The turbocharger oil supply strainer can become blocked, causing wear to the bearings due to lack of lubrication.
Campaign #22V17800023/03/2022
FUEL SYSTEM, GASOLINE:DELIVERY:HOSES, LINES/PIPING, AND FITTINGS
Volkswagen Group of America, Inc. (Volkswagen) is recalling certain 2013-2015 Audi S8 and A8 vehicles. The fuel supply line for the high pressure fuel pump may become porous over time, resulting in a fuel leak.
Campaign #18V43000025/06/2018
VISIBILITY:SUN/MOON ROOF ASSEMBLY
Volkswagen Group of America, Inc. (Volkswagen) is recalling certain model year 2013-2014 Audi A8 and S8 vehicles equipped with a standard sunroof, manufactured March 12, 2013, through July 15, 2013. These vehicles are equipped with a standard sunroof glass panel that may shatter.
Campaign #13V44800023/09/2013
Enter your VIN at NHTSA.gov to check recalls specific to your vehicle.
🔧
A mechanic who knows YOUR exact car
Answers tuned to your year, make, model & trim — not generic advice. Save your garage so it always has the right context.
Get ahead of Audi S8 problems — free
Leave your email and we'll alert you the moment there's a new recall or known issue for your Audi S8. Free, no account needed.
According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2018 Audi S8 has 1 documented issue. The documented issue is: 2013-2018 S8 Warm-Soak Long-Crank or No-Start - Fuel Diagnosis Required. None are rated critical, but regular maintenance is recommended.
Is the Audi S8 reliable?
The 2018 Audi S8 has 1 known issue compiled from NHTSA recalls, manufacturer TSBs, and owner forum reports. No issues are rated critical, suggesting generally good reliability. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
What is the 2013-2018 Audi S8 2013-2018 S8 Warm-Soak Long-Crank or No-Start - Fuel Diagnosis Required?
Audi TSB 2046724/5 covers sporadic warm-engine no-start or long cranking after the vehicle sits without fully cooling. A rich-mixture DTC may occur, but often there is no DTC. Audi’s procedure distinguishes fuel in the oil from a short-trip profile, ECM software, high-pressure in… Severity: medium.
Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.