BMW 4 Series: common problems, best years and what to check
Coupé, Convertible and Gran Coupé versions of the 3 Series. Covers 2013–2024 cars: every popular engine, its known faults with typical UK repair costs, and how each year has held up on Britain's roads.
Updated November 2026 · By the Carnod team · How we build this guide
Is the BMW 4 Series a good used buy?
Best buy
2016–2020 420d/420i Gran Coupé
Avoid
2013–2014 N47 420d
Who it suits: Drivers wanting a sporty, stylish premium coupé with BMW handling.
What's good
- Excellent to drive
- Gran Coupé is practical
- Frugal 420d
- Quality interior
What's not
- G22 grille is divisive
- Run-flat ride
- Tight rear seats in coupé
- Expensive options
By the numbers
- #76 most common model on UK roads, with about 112k licensed (DfT).
- The biggest surviving year is 2016: 18.1k cars still licensed.
- The most expensive common fault: Timing chain stretch (rear-mounted, engine-out) (up to £3,500).
BMW 4 Series common problems by generation and engine
BMW 4 Series F32/F33/F36 (2013–2020) · coupé/convertible/Gran Coupé
How to spot it: 13 plate to 20 plate. Low, wide coupé with headlights joined to small kidney grilles.
420d (2013–2014) (N47, diesel, 2013–2014)
Economical, but the rear timing chain can fail
- Timing chain stretch (rear-mounted, engine-out)£1,500–£3,50060k+ · Check: Listen for rattle at start; ask for chain history
420d / 418d (B47, diesel, 2015–2020)
Strong, frugal and much better than the N47
- EGR cooler (recall on many)£0–£1,200any · Check: Check EGR recall done
- Swirl / DPF faults on short trips£300–£1,50070k+
420i / 430i (B48, petrol, 2016–2020)
Smooth and reliable four-cylinder
- Coolant leaks from heater pipes / thermostat£250–£70050k+
BMW 4 Series G22/G23/G26 (2020–) · coupé/convertible/Gran Coupé; i4
How to spot it: 20 plate onwards. Huge vertical kidney grille.
420d (B47, diesel, 2020–)
Strong, frugal and much better than the N47
- EGR cooler (recall on many)£0–£1,200any · Check: Check EGR recall done
- Swirl / DPF faults on short trips£300–£1,50070k+
420i / M440i (B48, petrol, 2020–)
Smooth and reliable four-cylinder
- Coolant leaks from heater pipes / thermostat£250–£70050k+
Costs are typical UK independent-garage prices including parts and labour. Main dealers usually charge more.
Best and worst BMW 4 Series years
How many BMW 4 Seriess from each year are still licensed today (DfT), coloured by how well that year survives compared with similar cars of the same age.
No year clearly outlasts similar cars. No year falls off the road noticeably faster than similar cars.
BMW 4 Series MOT pass rate and common failures
First-time pass rate (2025)
Average UK car of the same age
MOT tests analysed (2013+ cars)
BMW 4 Seriess pass their MOT first time 6 points more often than the average UK car of the same age (84% vs 78%). Older cars fail more, so we compare like with like.
| First registered | Pass rate | Average UK car that age | Median mileage |
|---|---|---|---|
| 2013 | 77% | 66% | 97k miles |
| 2014 | 79% | 69% | 88k miles |
| 2015 | 81% | 72% | 83k miles |
| 2016 | 84% | 75% | 75k miles |
| 2017 | 85% | 78% | 65k miles |
| 2018 | 85% | 81% | 54k miles |
| 2019 | 85% | 84% | 45k miles |
| 2020 | 87% | 86% | 36k miles |
| 2021 | 89% | 87% | 30k miles |
| 2022 | 89% | 89% | 23k miles |
Pass rate by fuel
Diesel
Petrol
Diesel hybrid
Fuels differ in age and mileage mix, so treat this as a pattern rather than a like-for-like comparison.
Most common MOT failures
- Tyres: has ply or cords exposed2.92 per 100
- Tread depth below requirements of 1.6mm2.52 per 100
- Tyres: has a cut2.33 per 100
- Tyres: has a bulge1.59 per 100
- Shock absorbers: has a serious fluid leak1.42 per 100
- Brake pads: less than 1.5 mm thick1.18 per 100
- Washers: provides insufficient washer liquid1.01 per 100
- Headlamp aim: too high0.76 per 100
Most common advisories
- Tread depth below requirements of 1.6mm24.49 per 100
- Brake pads: less than 1.5 mm thick8.49 per 100
- Brake discs: in such a condition that it is seriously weakened8.4 per 100
- Pins and bushes: pin or bush excessively worn4.47 per 100
- Tyres: has a tear3.71 per 100
- Non-component advisories: Play in steering rack inner joint(s)3.59 per 100
- Shock absorbers: has a serious fluid leak3.45 per 100
- Tread depth: tread pattern not visible over the whole tread area when minimum depth required is 1.0mm3.44 per 100
Source: DVSA anonymised MOT results for 2025 (normal car tests). First-time pass counts faults fixed during the test as fails. Contains public sector information licensed under the Open Government Licence v3.0.
Does the BMW 4 Series have a timing belt or chain?
| Engine | Type | When | Cost |
|---|---|---|---|
| N47 | chain | check from 60k | £1,500–£3,500 |
| B47/B48 | chain | durable | £900–£1,800 |
BMW 4 Series running costs
Road tax (from April 2017)
Road tax (before April 2017)
Insurance groups
Real-world economy
Servicing (independent)
Tyres
Warranty when new
Is the BMW 4 Series ULEZ compliant?
- Petrol and hybrid: compliant if Euro 4 — nearly all petrol cars from 2006, many from 2001.
- Diesel: compliant only if Euro 6 — generally cars first registered from September 2015; earlier diesels pay £12.50 a day in London's ULEZ.
- Same standards apply in Birmingham and Bristol Clean Air Zones (which charge private cars) and Scotland's LEZs in Glasgow, Edinburgh, Aberdeen and Dundee (which fine them). Check the exact car on TfL's vehicle checker.
Safety and practicality
Euro NCAP
Boot
Seats
BMW 4 Series vs rivals
| Model | On UK roads | Insurance | Boot | Best buy |
|---|---|---|---|---|
| BMW 4 Series | 112k | 29–43 | 445 l | 2016–2020 420d/420i Gran Coupé |
| Audi A5 | 122k | 29–42 | 465 l | 2017+ F5 Sportback 40 TDI |
| Mercedes C-Class Coupé | — | — | — | Guide coming soon |
| Lexus RC | — | — | — | Guide coming soon |
| VW Arteon | — | — | — | Guide coming soon |
| BMW 3 Series | 405k | 26–40 | 480 l | 2015–2019 F30 320d (B47) or 2019+ G20 320d |
What to check when buying a used BMW 4 Series
- Prefer 2015+ B47
- Run-flat tyre condition
BMW 4 Series FAQ
›Is the BMW 4 Series reliable?
Generally, if you pick the right version. Best buy: 2016–2020 420d/420i Gran Coupé. Avoid: 2013–2014 N47 420d.
›What is the BMW 4 Series MOT pass rate?
84% of BMW 4 Seriess passed their MOT first time in 2025 (108,513 tests), better than the 78% average for cars of the same age. The most common failure: tyres: has ply or cords exposed.
›What are the most common BMW 4 Series problems?
The costliest known faults are Timing chain stretch; Swirl / DPF faults on short trips. Each one is listed by engine with typical UK repair costs above.
›Does the BMW 4 Series have a timing belt or chain?
N47: chain; B47/B48: chain.
›What is the best year BMW 4 Series to buy?
By DfT survival data, 2020, 2023, 2024 cars have outlasted comparable cars best. Condition and history still matter more than the year.
›How much does a BMW 4 Series cost to run?
Real-world economy: 420d 50–58 mpg; 420i 38–44 mpg. Insurance groups 29–43. A minor service is about £230–£320 at an independent garage.
›How much is road tax on a BMW 4 Series?
Cars registered from April 2017 pay £200 a year (more if the list price was over £40k). Older cars pay by CO2 band, from £20 to £790.
›Is the BMW 4 Series ULEZ compliant?
Petrol and hybrid: compliant if Euro 4 — nearly all petrol cars from 2006, many from 2001. Diesel: compliant only if Euro 6 — generally cars first registered from September 2015; earlier diesels pay £12.50 a day in London's ULEZ.
How we build this guide
We combine official UK data with what independent garages see most often on this model.
- How many are still on the road: DfT vehicle licensing statistics, by year first used. The survival comparison is against cars of the same age.
- MOT pass rates, failures and mileage: DVSA anonymised MOT results — every normal car MOT in Great Britain for the year, compared with all cars of the same age.
- Road tax: GOV.UK rates from April 2026. ULEZ: TfL and Clean Air Zone emission standards.
- Faults and repair costs: known problems by engine code, priced at typical UK independent-garage rates including parts and labour.
- Insurance groups, mpg, servicing and tyres: typical ranges, not quotes. Your car's exact figures depend on the version and where you live.
This is a buying guide, not a mechanical inspection. A specific car's MOT history tells you far more than any model average — run a free check on it before you go and see it.
Sources: licensed counts and survival from DfT vehicle licensing statistics; road tax from GOV.UK (April 2026 rates). Faults, costs, mpg and insurance groups are typical ranges, not quotes. A guide, not a mechanical inspection.