BMW 320i common problems and MOT failures
What goes wrong on a used BMW 320i, year by year: known faults from UK buying guides, the parts flagged at MOT more than on other cars (from 68,793 MOTs done during 2023–2025), and what to check before you buy one.
Pick the year
Most years have their own guide. The year is when the car was first registered (it’s on the logbook, or check the reg below).
20232022202120202019201820172016201520142013201220112010200920082007
What usually goes wrong with a BMW 320i?
Known faults reported by owners, mechanics and UK buying guides, in our own words. Most apply to certain years or engines only, so check which the car has.
- Cars registered 2012–2019 · 2.0 petrol and diesel
Timing chain wear
The four-cylinder petrol and diesel engines can suffer timing chain wear, especially with late oil changes. A failed chain is an engine-out repair.
At the viewing: Listen for a rattle or whine from the back of the engine, especially from cold. Ask for oil changes on time.
- Cars registered 2007–2011 · 2.0 diesel (2007 on)
Timing chain (N47 diesel, 318d/320d)
The 2.0 diesel's timing chain is at the back of the engine and is a known weak point. Replacing it costs around £1,000.
At the viewing: Start the engine from cold and listen for a rattle from the back.
- Cars registered 2007–2011 · All engines
Battery cable and blower wiring recalls
About 312,000 cars were recalled for a faulty positive battery cable and nearly 280,000 for a heater blower connector. Others covered side airbag wiring, the brake servo, the propshaft joint and VANOS units.
At the viewing: Ask a BMW dealer to check the VIN for outstanding recalls.
Source: Haynes: BMW 3 Series Mk5 common problems (2004-2011)
- Cars registered 2012–2019 · Diesel
Blocked EGR valve or particulate filter (diesel)
Diesels used mostly for short trips can block the EGR valve or clog the particulate filter, causing poor running.
At the viewing: Ask what journeys it’s done and watch for warning lights or a lack of power.
If it needs doing: DPF clean or regeneration, about £160–£500. ClickMechanic
- Cars registered 2007–2011 · 2.0 petrol
Misfires (N43 petrol, 320i)
The 2.0 petrol can misfire from faulty injectors and coil packs.
At the viewing: Check for a rough idle or warning light.
- Cars registered 2007–2011 · Six-cylinder petrol
Oil leaks (six-cylinder petrol)
The six-cylinder petrols leak oil from the cam cover and the oil filter housing.
At the viewing: Look under the bonnet and the car for oil.
- Cars registered 2007–2011 · Diesel
Flat battery from the fuel filter heater (diesel)
A faulty fuel filter heater can drain the battery.
At the viewing: Ask whether it has had flat batteries.
Source: Haynes: BMW 3 Series Mk5 common problems (2004-2011)
- Cars registered 2007–2011 · Manual gearbox
Clutch and dual-mass flywheel
A faulty dual-mass flywheel can make the clutch seize. Both need replacing.
At the viewing: Feel for judder or a heavy, odd clutch, and listen for rattles at idle.
Source: Haynes: BMW 3 Series Mk5 common problems (2004-2011)
- Cars registered 2012–2019
Noisy differential
A whine from the rear as the car passes you can mean the differential has been neglected.
At the viewing: Ask someone to drive it past you slowly and listen for a whine from the back.
- Cars registered 2007–2011 · All engines
Clunks over bumps in the cold
Worn front anti-roll bar bushes clunk, more in cold weather.
At the viewing: Drive over bumps and listen.
Source: Haynes: BMW 3 Series Mk5 common problems (2004-2011)
2 more known faults
- Cars registered 2007–2011 · All engines
Exhaust drone
A damaged exhaust flexi pipe drones when driving or idling.
At the viewing: Listen at idle and on the move.
Source: Haynes: BMW 3 Series Mk5 common problems (2004-2011)
- Cars registered 2020–2023 · All engines
Electrical and infotainment glitches
In What Car?'s survey 13% of petrol and plug-in hybrid cars had a fault, mostly minor electrical, engine and infotainment glitches.
At the viewing: Test the infotainment and all the electrics, and make sure no warning lights show.
BMW 320i MOT pass rate by year
Of the years since 2005 with plenty of MOT tests, the 2016 BMW 320i did best (86% passed first time, 9 points above all 2016 cars) and the 2020 did worst (87%, 0 points above all 2020 cars). Older cars fail more, so compare each year with all cars registered the same year.
| Year | Pass first time | All cars that year | MOT tests |
|---|---|---|---|
| 2023 | 93% | 92% +1 | 150 (small sample) |
| 2022 | 90% | 89% +1 | 3,051 |
| 2021 | 89% | 87% +2 | 12,035 |
| 2020 | 87% | 87% +0 | 15,890 |
| 2019 | 88% | 85% +3 | 17,381 |
| 2018 | 88% | 83% +5 | 7,865 |
| 2017 | 87% | 80% +7 | 9,049 |
| 2016 | 86% | 77% +9 | 1,735 |
| 2015 | 82% | 74% +8 | 206 (small sample) |
| 2014 | 84% | 70% +14 | 218 (small sample) |
| 2013 | 84% | 67% +17 | 307 (small sample) |
| 2012 | 85% | 64% +21 | 171 (small sample) |
| 2011 | 78% | 62% +16 | 176 (small sample) |
| 2010 | 77% | 60% +17 | 222 (small sample) |
| 2009 | 80% | 59% +21 | 109 (small sample) |
| 2008 | 69% | 57% +12 | 104 (small sample) |
| 2007 | 67% | 57% +10 | 124 (small sample) |
Questions to ask the seller before buying a BMW 320i
Ask before you travel to see it. A seller who knows the car will have answers, and receipts.
- Has the timing chain been checked or replaced, and have oil changes been on time?
- Has the timing chain been replaced?
- Have the battery cable and blower recalls been done?
- Have the injectors or coils been replaced?
- Have any oil leaks been fixed?
- Can I see the service history and receipts for any big jobs?
Looking at a BMW 320i?
Check the actual car: its own MOT history and what to ask the seller. Free, no sign-up.
Where this comes from: MOT figures are the DVSA’s anonymised results for every MOT test done in Great Britain during 2023–2025, grouped by the year each car was first registered. How many are on the road is from the Department for Transport’s vehicle licensing statistics. Known faults are from UK buying guides, in our own words, with links. How we score