Audi Q8 S Line 50tdi MHEV Quattro A (2021)

277 real MOT outcomes analysed • 90% first-time pass rate

2021 Audi Q8 S Line 50tdi MHEV Quattro A

CarHunch analysed 277 real MOT records for the 2021 Audi Q8 S Line 50tdi MHEV Quattro A. This breakdown of actual test outcomes — pass rates, defect profiles, mileage data — isn't published anywhere else.

The 2021 Audi Q8 50TDI is a genuinely reliable proposition, posting a 90% first-time pass rate that comfortably beats the UK average of 80%, and dangerous defects are rare at just 4.3% of vehicles ever flagged. This diesel-only cohort shows no weak spots between fuel types, since virtually all examples run the TDI engine.

At 38,965 miles average for a three-year-old car, these Q8s are running well within expected mileage, which supports their strong pass performance. The 0.15 average failures per test and 1.3 advisories suggest routine maintenance keeps issues at bay—if you're considering one, check the service history closely to confirm that pattern has been followed.

Generally reliable 10% above UK average
90%
pass MOT first time
UK average: ~80%
37,047
typical mileage
28,690–47,737 middle half
4.3%
ever had a dangerous defect
recorded at any MOT
0.15
avg MOT failures per car
over 2 tests on record

What to check before buying a 2021 Audi Q8 S Line 50tdi MHEV Quattro A

Practical pre-purchase checks for this age and model.

  • 📋 Check the full MOT history. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. Enter the reg below for a full AI analysis.
  • 🔍 Inspect for corrosion in person. Brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that's expensive to fix and can fail an MOT.
  • 🛞 Check tyres and brakes. The most common advisory items at this age. Budget for replacement if they're near the limit — factor this into your offer price.
  • 📄 Run an HPI check. The MOT history won't show outstanding finance, insurance write-offs, or stolen status — an HPI check will.

Before you buy a Audi Q8 S Line 50tdi MHEV Quattro A

MOT history is one piece of the puzzle. These checks can reveal what CarHunch can't.

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Pass Rate by Fuel Type

Fuel type Vehicles Pass rate Avg failures
Diesel (99%) 275 90% 0.15
Electric Diesel (0%) 1 100% 0
Gas Bi-Fuel (0%) 1 100% 0

Mileage Distribution

Most 2021 Audi Q8 S Line 50tdi MHEV Quattro A vehicles sit in the blue band. If the car you're looking at is outside it, it's either unusually low or high mileage for its age.

28,690
low mileage
37,047
typical
47,737
high mileage

Half of all 2021 Audi Q8 S Line 50tdi MHEV Quattro A vehicles fall between 28,690 and 47,737 miles.

MOT History Averages

2
Avg MOT tests per vehicle
0.15
Avg failures per vehicle
1.3
Avg advisories per vehicle

Found a specific Audi Q8 S Line 50tdi MHEV Quattro A?

Enter the reg to see its individual MOT history, AI Hunches, and how it compares to this cohort.

UK

Other model years — Audi Q8 S Line 50tdi MHEV Quattro A:

2023