Should I check the MOT history before buying a 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA?

Yes. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. A full MOT history analysis will highlight patterns that a single test result won't reveal.

What corrosion should I look for when inspecting a 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA?

Check brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that is expensive to fix and can fail an MOT.

How are tyres and brakes typically on a 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA?

Tyres and brakes are the most common advisory items on vehicles of this age. Budget for replacement if they are near the limit, and factor this into your offer price.

Is the 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA reliable?

Based on MOT data from 781 vehicles, the 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA has a first-time MOT pass rate of 91.8%, indicating generally reliable for its class. Always check the full MOT history of any specific vehicle before buying.

Do I need an HPI check when buying a 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA?

Yes. The MOT history will not show outstanding finance, insurance write-offs, or stolen status. An HPI check covers these areas and should be part of any used car purchase.

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Audi A4 S Ln Black Ed 35tdi MHEV SA (2021)

781 real MOT outcomes analysed • 91.8% first-time pass rate

2021 Audi A4 S Ln Black Ed 35tdi MHEV SA

CarHunch analysed 781 real MOT records for the 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA. Real test outcomes — pass rates, defect profiles, mileage data — from verified DVLA records. Updated as new MOTs are recorded.
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AI Analysis Reliability Overview Check a Specific Reg Buyer's Checklist Pass Rate by Fuel Mileage Distribution MOT Averages Colour Breakdown Compare Models

This 2021 Audi A4 S Line diesel is noticeably more reliable than the UK average, with an 86% first-time pass rate compared to the 80% baseline—a solid 6-percentage-point advantage. The 12.7% of vehicles that have experienced a dangerous defect is well within acceptable bounds, so there's no red flag for safety concerns here.

At nearly 40,000 miles median, these cars are showing typical mileage for their age, and the modest 0.24 average failures per vehicle suggests owners aren't facing major mechanical issues. Before buying, get a pre-purchase inspection focused on the diesel engine's fuel system and emissions equipment—these tend to generate the occasional advisory—but this generation is punching above its weight for the money.

The 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA passes its MOT first time more often than most UK vehicles (91.8% vs ~80% average) — and when it does fail, it's usually something minor and cheap to fix.

⚠️ Around 1 in 8 of these vehicles have had a dangerous MOT failure at some point — usually tyres or brakes, and often a one-off issue rather than a persistent problem. The group stats won't tell you which one you're looking at.

First-time pass

91.8%

UK average ~80%

Better than average

Dangerous (ever)

12.7%

At least once in MOT history

Check this vehicle

Avg failures / car

0.24

Over 2.1 tests on record

Low

Typical mileage

39k

Middle half: 30k–51k

For context

✅ Good baseline reliability. A 91.8% first-time pass rate puts this well above the UK average — it's a well-sorted vehicle in this age bracket.

🔧 Expect consumable spend. An average of 1.5 advisories per vehicle tells you wear items (tyres, brakes) get flagged regularly. Budget for them — they're not surprises.

🔍 The dangerous defect figure is real. Most are one-off tyre failures or brake issues — not structural problems. But it's exactly why checking the individual vehicle's history is essential, not optional.

These stats describe 781 vehicles as a group. The specific vehicle you're looking at could be the one good example or the one outlier. Run its registration to find out.

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See this vehicle's full MOT history & AI hunches

Spot recurring advisories, hidden issues, and how it compares to 781 Audi A4 S Ln Black Ed 35tdi MHEV SA cars.

Before you buy a 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA

Based on MOT data from 781 vehicles — here's what to check.

📋 Check the full MOT history. 12.7% of these vehicles have had a dangerous defect recorded - recurring advisories often signal problems years before they become failures.
Search the reg on CarHunch for the full MOT history, reliability stats and a free AI-powered analysis of that exact vehicle.
🔍 Brake pipes, sills and subframes are the key areas on a vehicle this age — structural rust is hard to spot without getting underneath. A mechanic will check all of this before you commit, and give you a concrete basis to negotiate on price. Inspection →
📄 Outstanding finance, insurance write-offs and clocking won't appear in the MOT records — a dedicated history check covers all of this. Our link gets you 20% off automatically. History Get 20% off via CarHunch

Pass Rate by Fuel Type

Fuel type	Vehicles	Pass rate	Avg failures
Diesel (99%)	776	91.7%	0.24

Colour Breakdown

Based on 2,079 Audi A4 S Ln Black Ed 35tdi MHEV SA vehicles registered in the UK — across all years. From DVLA registration records.

Grey 28%

583

Black 27.9%

580

Blue 22.8%

475

White 19.6%

407

Red 1.6%

Mileage Distribution

Most 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA vehicles sit in the blue band. If the vehicle you're looking at is outside it, it's either unusually low or high mileage for its age.

39,167

typical

29,687

low mileage

50,980

high mileage

Half of all 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA vehicles fall between 29,687 and 50,980 miles.

Is the mileage you're seeing normal?

✓ Under 29,687 miles — lower than most. Could be great, or could be a vehicle that rarely moved. Check test frequency and mileage progression in the MOT history.

✓ 29,687–50,980 miles — normal for age. This is where most 2021 Audi A4 S Ln Black Ed 35tdi MHEV SAs sit.

⚠ Over 68,823 miles — higher than typical. Not necessarily a problem, but check service history and look out for advisory build-up on tyres and brakes.

MOT History Averages

2.1

Avg MOT tests per vehicle

0.24

Avg failures per vehicle

1.5

Avg advisories per vehicle

Other model years — Audi A4 S Ln Black Ed 35tdi MHEV SA: All A4 S Ln Black Ed 35tdi MHEV SA years → Which year to buy? →

2022 2023 2024

Or browse all models: Audi →

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See how the 2021 Audi A4 S Ln Black Ed 35tdi MHEV SA stacks up against a rival.

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