Audi A4 vs BMW 3 Series: which is the better used buy?

On DVSA MOT records the BMW 3 Series is the more reliable used buy: it passes its first MOT 3.3 percentage points more often than the Audi A4 once both are compared against what the national fleet scores at the same age. That comparison covers 67,647 real tests, not a survey.

MOT first-time pass rate

Counted from DVSA’s anonymised MOT test records. “vs age-matched” compares each model against what the national fleet scores at the same age — the only fair better-or-worse number, because an older fleet fails more whatever its build quality.

Model	Pass rate	Age-matched national	Difference	Tests
Audi A4	77.3%	75%	+2.3	24,990
BMW 3 Series	79.1%	73.5%	+5.6	42,657

Source: DVSA MOT Anonymised Data 2025 (Open Government Licence v3.0). National first-time pass rate 77.3%. Applies to Great Britain — Northern Ireland is tested by the DVA under a separate manual.

Audi A4

B9 (2015–2023) · D-segment executive saloon and Avant estate. One of the most popular used premium cars in the UK alongside the BMW 3 Series. Available as saloon and Avant estate. Key engines: 2.0 TFSI petrol (150–252 PS), 2.0 TDI diesel (136–190 PS), 35 TFSI mild hybrid (150 PS), 40 TFSI (190 PS), 40 TDI (204 PS).

The Audi A4 B9 is a premium, refined executive car with strong build quality, but it requires disciplined Audi specialist maintenance to keep running costs manageable. The 2.0 TDI diesel is reliable on motorway mileage but has documented timing belt (not chain) service requirements — belt failure on the B9 2.0 TDI is an engine-write-off event. The 2.0 TFSI mild hybrid (post-2019) is the better choice for mixed UK driving. Avoid any B9 A4 without full documented service history — Audi's repair costs are high and an unmaintained A4 can quickly become very expensive.

What goes wrong

2.0 TDI timing belt service (interference engine)critical
No audible warning — belt failure is sudden and catastrophic. Prevention through scheduled service is the only protection.
All B9 A4 2.0 TDI (2015–2023) · Audi recommended interval: every 80,000 miles or 4 years (whichever first). Many specialists recommend 55,000 miles or 4 years in UK stop-start conditions. · £700–£1,200 timing belt kit (preventive); £8,000–£15,000+ engine replacement if belt fails (the 2.0 TDI is an interference engine — belt failure destroys the engine)
Check: Ask for documented timing belt replacement history. If the car is at 55,000+ miles with no record of a belt change, factor the service into the purchase price or walk away. The 2.0 TDI's timing belt is one of the most important pre-purchase checks on any B9 A4. The petrol TFSI engines use a timing chain — this concern is diesel-specific.
MMI infotainment and virtual cockpit freezingminor
MMI screen freeze; navigation crash; virtual cockpit going blank; MMI reboot loops
2015–2019 (older MMI generations) · Not mileage-related — software degradation over time · £0 — software update at Audi dealer; hardware replacement £600–£1,200 if MMI control unit fails
Check: Test all MMI functions during the test drive — navigation, Bluetooth, media, climate control (which is MMI-integrated on many trims). Ask if the latest Audi software update has been applied. Most MMI issues are software-related and resolved by an update.
S-Tronic DSG dual-clutch juddermajor
Shudder or hesitation when pulling away from standstill; jerky low-speed changes; clutch grab in first gear
2015–2021 (7-speed S-Tronic DL382/DQ381 automatic) · Above 35,000 miles in urban use; can appear earlier without service · £400–£700 DSG fluid and filter change + software calibration; £1,500–£3,500 mechatronic or clutch pack replacement
Check: Test the S-Tronic at walking pace in traffic and pulling away on a slope. Any shudder is the known Audi/VAG DSG judder. Ask for DSG service history — fluid change every 35,000 miles is the minimum. An unmaintained S-Tronic above 60,000 miles is a significant risk.
High-pressure fuel pump failure (2.0 TFSI EA888)major
Hard starting; rough idle; fuel pressure warning; misfires
2015–2019 (EA888 Gen 3 TFSI) · Above 60,000 miles · £600–£1,200 high-pressure fuel pump; £200–£400 low-pressure fuel pump
Check: Test cold start behaviour. Any hesitation or extended cranking before starting suggests fuel system issues. Ask about any fuel pressure warning codes in the service history.

Typical asking price:: B9 2015–2018 2.0 TDI: £8,000–£16,000 | B9 2019–2021 facelift: £15,000–£26,000 | Avant estate: £1,000–£2,500 premium over saloon
Real-world economy:: 49–57 mpg (2.0 TDI real-world UK motorway mixed); 38–47 mpg (35 TFSI MHEV real-world)
Vehicle tax:: £200/year standard rate from the second year, hybrids included — the alternative-fuel discount ended on 1 April 2025. Cars registered 2001–2017 pay a CO2 band, roughly £20–£790/year (2026/27 rates).
Best years:: 2019, 2020, 2021
Years to avoid:: 2015, 2016

Full A4 fault guide Used Audis

BMW 3 Series

F30 (2012–2019) / G20 (2019–present) · D-segment executive saloon and touring estate. The most popular used premium car in the UK by volume. Available in a wide range of engines: 316i, 318i, 320i, 330i petrols; 316d, 318d, 320d, 330d diesels; 330e plug-in hybrid. Saloon, Touring (estate), and Gran Turismo body styles.

The BMW 3 Series is one of the best driver's cars in its segment but requires disciplined maintenance to avoid expensive repairs. The 320d diesel is by far the most popular UK-market variant — reliable at motorway mileage but requires a full service and timing chain history. The N47 diesel engine (pre-2015) had a timing chain tensioner failure issue at the rear of the engine — an expensive repair. The B47 diesel (post-2015) is significantly more reliable. On petrols, the B48 (post-2015 G20) is excellent. The key rule: full BMW dealer or BMW-specialist service history is essential. An unmaintained 3 Series is an expensive liability.

What goes wrong

N47 diesel timing chain failure (F30 2012–2015)critical
Chain rattle on cold start; rattling from rear of engine; engine management light; in severe cases, sudden engine failure
F30 2012–2015 with N47 diesel (316d, 318d, 320d) · From 60,000 miles; can occur earlier if oil changes were delayed · £3,000–£6,000 timing chain replacement (rear-mounted chain requires engine removal); up to £10,000+ if the chain has jumped and damaged the engine
Check: This is the single most critical check on any F30 N47 diesel. The N47 chain is rear-mounted — listen for chain rattle at idle with the bonnet up. Ask for proof of timing chain replacement in the service history. If the chain has not been replaced and the car has over 75,000 miles, budget for the repair or walk away. The B47 diesel (post-2015 on the F30 facelift and all G20) is unaffected.
Electric water pump failure (N20/B46/B48 petrols)major
Coolant warning light; engine overheating; steam from engine bay; loss of heat from heater
F30 2012–2019 petrol models (N20 engine) · From 50,000 miles; often fails between 60,000–95,000 miles · £600–£1,200 water pump replacement
Check: Check coolant level and condition. Ask about any history of overheating or coolant warning lights. The electric water pump on N20 engines is a known maintenance item — not catastrophic if caught early, but a failed pump can cause overheating if ignored. Budget for proactive replacement on high-mileage N20 cars.
320d/318d high-pressure fuel pump failure (N47)major
Hard starting; rough idle; engine cutting out; fuel pressure fault codes
F30 N47 diesel 2012–2015 · Above 75,000 miles · £800–£1,500 high-pressure fuel pump replacement
Check: Check for any hesitation or hard-starting behaviour on the test drive. N47 high-pressure fuel pump failures are common above 75,000 miles. If this is a known issue on the specific car, negotiate accordingly.
EGS automatic gearbox selector module failure (ZF 8HP)moderate
Gearbox warning light; "Transmission malfunction" message; car stuck in one gear; intermittent gear selection issues
F30 2012–2019 (ZF 8-speed automatic) · Above 60,000 miles · £400–£1,200 EGS module replacement; ZF gearbox service (fluid + filter) £300–£500
Check: Test the automatic gearbox through its full range — all gears, Sport mode, manual paddle shifts. Any hesitation, warning lights, or erratic behaviour requires investigation. Ask for ZF gearbox service history (fluid change every 35,000 miles prolongs life significantly).

Typical asking price:: F30 2015–2018 320d: £8,000–£15,000 | F30 2018–2019 facelift: £12,000–£18,000 | G20 2019–2022: £15,000–£28,000
Real-world economy:: 47–57 mpg (320d real-world UK mixed motorway); 35–44 mpg (320i petrol real-world)
Vehicle tax:: £200/year standard rate from the second year, hybrids included — the alternative-fuel discount ended on 1 April 2025. Cars registered 2001–2017 pay a CO2 band, roughly £20–£790/year (2026/27 rates).
Best years:: 2019, 2020, 2021, 2022
Years to avoid:: 2012, 2013, 2014

Full 3 Series fault guide Used BMWs

Which one suits you

Audi A4

Good for: Executive-segment buyers who want a refined, well-built premium saloon or estate. Motorway commuters (A4 Avant TDI is excellent value for high-mileage motorway use). Buyers who will use an Audi specialist for servicing.

Less good for: Buyers who cannot verify the 2.0 TDI timing belt service history. S-Tronic automatic buyers without DSG service history above 35,000 miles. Buyers wanting the lowest total cost of ownership — a Skoda Superb or Skoda Octavia diesel estate offers broadly similar space and refinement for significantly lower running costs.

BMW 3 Series

Good for: Buyers who want a genuine driver's car and are prepared to maintain it properly. Motorway-mile buyers who will use the 320d's diesel efficiency on long UK commutes. Buyers with a BMW specialist garage lined up for servicing.

Less good for: Buyers who want the lowest total cost of ownership — a Toyota Corolla or Skoda Octavia will cost meaningfully less to run. F30 N47 diesel buyers without verified timing chain history — this is a potentially catastrophic repair. First-time BMW buyers who plan to service it at the cheapest possible garage — BMW models require BMW-specific knowledge and fluids.

Frequently Asked Questions

Which is more reliable, the Audi A4 or the BMW 3 Series?

The BMW 3 Series. It passes its first MOT 3.3 percentage points more often than the Audi A4 once both are age-adjusted, across 67,647 DVSA-recorded tests.

What is the MOT pass rate for the Audi A4?

77.3% of Audi A4s pass their MOT first time, from 24,990 tests in DVSA's records. The national first-time rate is 77.3%, but cars of this model's age average 75% — so it runs 2.3 points better than its age group.

What is the MOT pass rate for the BMW 3 Series?

79.1% of BMW 3 Seriess pass their MOT first time, from 42,657 tests. Against the 73.5% that cars of its age average, it runs 5.6 points better.

Which years should I avoid?

For the Audi A4, 2015–2016 B9 launch cars: more reported MMI infotainment issues, some ZF gearbox calibration complaints on early DSG/S-Tronic automatics, and earlier fuel system issues on the 2.0 TDI before production revisions. For the BMW 3 Series, 2012–2014 F30 with N47 diesel: the N47 2.0-litre diesel used in 316d, 318d, and 320d had a rear-mounted timing chain that stretched and failed prematurely, often at 60,000–95,000 miles. The repair requires removing the engine — costs of £3,000–£6,000 were common. Many N47 engines were replaced under extended warranty or goodwill; survivors without documented chain replacement are high-risk.

Which is cheaper to run?

The Audi A4 returns 49–57 mpg (2.0 TDI real-world UK motorway mixed); 38–47 mpg (35 TFSI MHEV real-world) in real UK driving; the BMW 3 Series returns 47–57 mpg (320d real-world UK mixed motorway); 35–44 mpg (320i petrol real-world). Vehicle tax: A4 — £200/year standard rate from the second year, hybrids included — the alternative-fuel discount ended on 1 April 2025. Cars registered 2001–2017 pay a CO2 band, roughly £20–£790/year (2026/27 rates).; 3 Series — £200/year standard rate from the second year, hybrids included — the alternative-fuel discount ended on 1 April 2025. Cars registered 2001–2017 pay a CO2 band, roughly £20–£790/year (2026/27 rates).. Insurance differs mainly by driver and postcode rather than by model, so treat any model-level insurance figure with caution.

MOT figures are counted from DVSA records and are the only measured statistic here. Prices, economy and tax bands are indicative and vary by specification, condition and where the car has lived. Last reviewed: 2026-08-14 / 2026-08-14.