Audi A4 S Line 35 TDI MHEV S A (2021)
2021 Audi A4 S Line 35 TDI MHEV S A
CarHunch analysed 1,291 real MOT records for the 2021 Audi A4 S Line 35 TDI MHEV S A. This breakdown of actual test outcomes — pass rates, defect profiles, mileage data — isn't published anywhere else.
This 2021 A4 S Line diesel hybrid is more reliable than average, with an 86.2% first-time pass rate that's 6.2 percentage points above the UK baseline—and only 10.9% of vehicles have ever recorded a dangerous defect, which is reassuringly low. The diesel engine itself shows no particular weakness compared to petrol alternatives, since the fuel breakdown is almost entirely diesel.
At 41,657 miles median for a three-year-old car, these are genuinely low-mileage examples, which explains why failures average just 0.24 per vehicle—most issues caught are minor advisories (1.7 per car, typically wear items). Before buying, get an independent inspection focused on the hybrid battery and dual-clutch transmission, as these complex systems won't show their true condition until higher mileage.
What to check before buying a 2021 Audi A4 S Line 35 TDI MHEV S 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 A4 S Line 35 TDI MHEV S A
MOT history is one piece of the puzzle. These checks can reveal what CarHunch can't.
CarHunch may earn a small commission if you buy via these links — at no extra cost to you.
Pass Rate by Fuel Type
| Fuel type | Vehicles | Pass rate | Avg failures |
|---|---|---|---|
| Diesel (100%) | 1,286 | 86.2% | 0.24 |
| Electric Diesel (0%) | 3 | 91.7% | 0.33 |
| Hybrid Electric (Clean) (0%) | 2 | 83.3% | 0.5 |
Mileage Distribution
Most 2021 Audi A4 S Line 35 TDI MHEV S 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.
Half of all 2021 Audi A4 S Line 35 TDI MHEV S A vehicles fall between 32,969 and 51,911 miles.
MOT History Averages
Found a specific Audi A4 S Line 35 TDI MHEV S A?
Enter the reg to see its individual MOT history, AI Hunches, and how it compares to this cohort.