OBD diagnostics · purchase protection

2018 Audi S5
Common Problems & Inspection Guide

Verify baseline vehicle system stability data. Learn what to check on the physical vehicle computer before signing a bill of sale.

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Platform Heritage

The Audi S5 is one of two high-performance variants of Audi's A5. The B8 and B9 generations were marketed as the coupé, cabriolet, and five-door fastback sedan versions of the B8 and B9 Audi S4 saloon and estate models, while the B10 S5 is the direct replacement of the B9 S4 models. Like all Audi "S" cars, they are only available with Audi's quattro four-wheel drive (4WD) system, here in S5 using a Torsen-based centre diff system. Most versions of the S5 are manufactured at Audi's plant in Ingolstadt, Germany; they are available as a coupé, cabriolet, and five-door sportback, which was previously not available in North America until the 2018 model year, which was released in the United States in mid 2017. The cabriolets are built at Audi's factory in Neckarsulm, Germany.

Source: Wikipedia intro extract · as of Jul 24, 2026

Key facts for this model year

26NHTSA owner complaints
2Safety recalls on file
8Top issue reports · Engine
$0Typical OEM recall remedy cost to you

0 average monthly buyer searches in the US (google ads data · as of Jul 24, 2026). Run a MotoMetrics scan for your VIN to see live repair exposure.

Verify the data — open primary sources · as of Jul 24, 2026

System Defect Summaries & Field Data

Active safety recalls on file: 2 (source: NHTSA Recalls API · as of Jul 24, 2026)

Top NHTSA complaint categories

Recent recall summaries

Campaign 19V547000 · AIR BAGS:FRONTAL:PASSENGER SIDE:INFLATOR MODULE · API record

Volkswagen Group of America, Inc. (Audi) is recalling certain 2018-2019 Audi RS5 Sportback, 2018 S5 Cabriolet, S5 Sportback, S5 Coupe, S4 Sedan, A5 Cabriolet, A5 Sportback, A5 Coupe, and 2017-2018 A4 Sedan and A4 Allroad vehicles. Oxidation on the Passenger Occupant Detection System (PODS) connecting cable may cause the software to misdiagnose a malfunction and disable the passenger air bag.

Campaign 21V874000 · SEATS · API record

Volkswagen Group of America, Inc. (Audi) is recalling certain 2017-2020 A4 Allroad, A4 Sedan, 2018-2019 RS5 Coupe, 2019 RS5 Sportback, 2018-2020 A5 Cabriolet, A5 Coupe, A5 Sportback, S4 Sedan, S5 Cabriolet, S5 Coupe, and Audi S5 Sportback vehicles. The cable connecting the seat heater to the Passenger Occupant Detection System (PODS) may have a contact fault, causing the software to misdiagnose a malfunction and disable the passenger air bag.

YouTube voice themes below are research hints only — verify against NHTSA data before citing.

On-Site Audi S5 Pre-Purchase Checklist

  1. Verify OBD-II readiness monitors are complete (not recently cleared) using a full protocol scan.
  2. Compare dashboard mileage to ECU-stored odometer modules where accessible.
  3. Pull permanent and pending DTCs — not only stored codes visible on the dash.
  4. Inspect systems related to ENGINE (NHTSA complaint cluster — verify during test drive and PPI).
  5. Inspect systems related to UNKNOWN OR OTHER (NHTSA complaint cluster — verify during test drive and PPI).
  6. Inspect systems related to AIR BAGS,SEAT BELTS,SEATS (NHTSA complaint cluster — verify during test drive and PPI).
  7. Inspect systems related to PARKING BRAKE,AIR BAGS,FUEL/PROPULSION SYSTEM (NHTSA complaint cluster — verify during test drive and PPI).
  8. Inspect systems related to POWER TRAIN,ENGINE (NHTSA complaint cluster — verify during test drive and PPI).
  9. Confirm recall remedy completed for AIR BAGS:FRONTAL:PASSENGER SIDE:INFLATOR MODULE (campaign 19V547000).
  10. Confirm recall remedy completed for SEATS (campaign 21V874000).
  11. Run a MotoMetrics on-site scan for Audi S5 before signing the bill of sale.

Audi OBD-II trouble code quick reference

  • P0420 — Catalyst system efficiency below threshold — top long-tail code across most makes
  • P0171 — Fuel system too lean — vacuum leaks and fuel trim diagnostics
  • P0300 — Engine misfire detected — inspect coils, plugs, and compression

Generic diagnostic context only — confirm stored, pending, and permanent codes with a full-protocol scan before purchase.

Alternative Inferences & Cross-Shopping Matrix

Adjacent model years for this nameplate and equivalent footprints shoppers compare across brands.

Generational cohorts

2017 Audi S5 2019 Audi S5 2020 Audi S5 2021 Audi S5

Class competitors

No cross-shop peers indexed in this segment yet.

Vehicle health varies wildly by individual history. Aggregate recall and complaint data cannot tell you whether the specific car on the lot had its monitors cleared or its odometer rolled back. Verify the physical or digital scan before you sign a bill of sale.

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