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BMW G20 3 Series buyer's guide

2019–present · 330i / xDrive, 330e / xDrive, M340i / xDrive (B46/B48, B58)

2019 BMW 318d sedan (G20)
2019 BMW 318d sedan (G20). Photo: Vauxford, CC BY-SA 4.0, via Wikimedia Commons (cropped, resized).

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Engines by year Model-year changes Known problems Other issues Warranty extensions Recalls Inspection checklist Red flags Which to buy Specs Paint codes Coding Ownership costs Sources

Models and engines by year

ModelUS model yearsEngine
330i / xDrive2019–presentB46/B48
330e / xDrive2021–presentB46/B48 plug-in hybrid
M340i / xDrive2020–presentB58

US-market models. Chassis codes: G20. Not sure which one you have? The VIN check decodes year, model and engine.

Model-year changes

Model yearWhat changed
2019Launch with the 330i (B48) and M340i (B58), on the CLAR platform with "lift-related" dampers as standard. Production started in October 2018; the M340i went on sale in spring 2019.8,9
2021–202248V mild-hybrid tech is added to most engines just before the facelift; rollout and timing vary by market.9,10
2023 (LCI)Facelift from July 2022. Slimmer LED headlights, new bumpers, and a standard Curved Display (12.3-in instruments plus 14.9-in center screen) with iDrive on BMW OS 8. New toggle gear selector. All US cars built in San Luis Potosí, Mexico. M340i has 48V mild hybrid.10,11,8
2025–2026iDrive moves to OS 8.5 for MY2025. For MY2026, US 330i and M340i production moved to Munich.8

US model years unless noted. "LCI" (Life Cycle Impulse) is BMW's name for a mid-cycle facelift.

Known problems and when they show up

Mileages are what the cited shops, specialists and owner forums report. They are typical ranges, not predictions for any one car.

B46/B48 engine

330i / xDrive (2019–present), 330e / xDrive (2021–present) · B46/B48 bulletins

ProblemWhen it shows upWhat to knowRepair prices
Coolant leak at the oil filter housingmost reports about 60,000–80,000 milesBMW SIB 11 10 25 (Dec 2025): the housing seal can press on the coolant bushing so it deforms and leaks. The fix is a new gasket set and a redesigned bushing. It covers B46/B48 in G01, G02, G20, G22, G23, G26, G29, G30, G45 and G60.1,2,3B58 / B48 oil filter housing (coolant leak)
Owners paid: indie shop $1,800–$3,300 · dealer $2,825–$3,950
Brittle coolant hoses and couplingsage and heat relatedPlastic connectors near hot parts crack and can burst.3,2No price yet
Turbo oil return line leak (early cars)early productionCaused by a mis-assembled gasket, fixed under warranty on early engines.3No price yet
Fuel tank vent (purge) valveany mileageEvap check-engine light. BMW NA extended the warranty on this valve to 15 yr/150,000 mi on many B46/B48/B58 cars (SIB 01 02 24 and later; listed on our job page).4B58 / B48 fuel tank vent valve (purge valve)

B58 engine

M340i / xDrive (2020–present) · B58 bulletins

ProblemWhen it shows upWhat to knowRepair prices
Coolant loss: oil filter housing, vent hose, water pump, expansion tankcommonly from about 60,000–80,000 miles; water pumps typically last about 75,000–100,000Often a slow "ghost" leak you smell but can't see. A pressure test finds it. Common sources are the plastic oil filter housing and its coolant vent hose, the water pump and the expansion tank.5,2,6B58 / B48 oil filter housing (coolant leak)
Owners paid: indie shop $1,800–$3,300 · dealer $2,825–$3,950
Valve cover gasket and PCVvalve cover gaskets about 60,000–100,000 milesOil on the spark plugs, burning-oil smell, low-oil warning. In November 2023 BMW NA mailed owners a 15 yr/150,000 mi warranty extension for the crankcase pressure control (PCV) valve (details and letter on our job page).7,5B58 valve cover / PCV failure
Owners paid: dealer $3,049–$4,450
Fuel tank vent (purge) valveany mileageEvap check-engine light. BMW NA extended the warranty on this valve to 15 yr/150,000 mi on many B46/B48/B58 cars (SIB 01 02 24 and later; listed on our job page).4B58 / B48 fuel tank vent valve (purge valve)

Known G20 issues beyond the engine

Owner-reported faults. RAC's owner survey lists: exhaust rattle on a cold start, rear differential oil leaks, creaking interior plastics, sunroof rattle, iDrive connectivity problems, Harman Kardon bass cutting out, and Cross Traffic Alert faults.9

B46/B48 coolant leak at the oil filter housing. BMW SIB 11 10 25 covers 330i (B46/B48) G20s. See the engine section.

Warranty extensions and service campaigns 30

Warranty extensions (17)

Showing 15 of 17.

Service campaigns (13)

Showing the 10 newest of 13. All bulletins for the G20 →

Filed by BMW with NHTSA. Extensions usually follow the car to later owners and can reimburse earlier repairs; a BMW dealer can confirm by VIN.

NHTSA safety recalls 26

  • Recall 26V056: engine starter 230I, 330I, 430I, 530I, X3, X4, Z4, 2021–2024. Please see the recall report for a complete list of all models.
  • Recall 25V636: engine starter 230I, 330I, 430I, 430I CONVERTIBLE, 530I, X3, X4, Z4, 2019–2022. The engine starter relay may corrode, causing the relay to overheat and short circuit.
  • Recall 25V202: starter-generator 330I, 430I, 530I, X3, 2025. The electrical connection between the starter-generator and battery may come loose.
  • Recall 24V576: engine starter software 740I, 840I, M340I, M340XI, X5, X6, X7, 2019–2021. BMW of North America, LLC is recalling certain 2019-2020 X5, X7, 2020 3 Series Sedan, X6, 2020-2021 7 Series Sedan, 2020 8 Series Convertible, 8 Series Coupe, and 2020 8 Series Gran Coupe vehicles.
  • Recall 23V770: steering gear 230I, 330I, X3, X4, 2024. The steering gear may not have been tightened properly, which can allow it to loosen.
  • Recall 23V584: receiver audio module (ram) ECU 228I, 330I, 430I, M340I, M440I, 2019–2022. The receiver audio module control unit software may fail to properly generate audible seat belt warnings to the driver to fasten their seat belt.
  • Recall 23V211: front seat frame 330I, M340I, X3, X4, 2019–2021. The seat frame may not have been welded properly to the seat rails.
  • Recall 23V118: body domain controller (bdc) ECU 330E, 330I, 430I, I4, M3, M340I, M440I, 2022–2023. During a service visit, a replacement electronic control unit (ECU) may have been installed with incorrect programming, which can cause the automatic door locking (ADL) function to not lock the doors as intended.
  • Recall 22V747: rearview camera software 330E, 2023. After shifting into reverse, the rearview camera software may cause a portion of the rearview image to be obstructed.
  • Recall 22V070: transmission mechatronics unit 330I, 530I, X3, X4, 2022. The mechatronics unit inside the transmission may not have been assembled properly, which could result in an internal leak.
  • Recall 21V598: engine management software 540I, 745LE, M340I, X3, X4, Z4, 2019–2021. During engine start, the engine management software may cause loss of braking assist.
  • Recall 21V554: passenger seat safety belt retractor 228I, 230I, 330E, 330I, 430I, 530I, 540I, M2, M235I, M240I, M3, M340I, M4, M440I, X1, X2, Z4, 2021. The passenger seat belt Automatic Locking Retractor (ALR) may deactivate early, before the webbing fully retracts.

Showing the 12 newest of 26.

Matched from NHTSA's public recall file by model and model year. A recall may cover only some cars from a year, and it may already have been done on yours. Check by VIN →

Test drive and inspection checklist

  1. Run the VIN for open recalls. Open safety recalls are free at any BMW dealer. Check on NHTSA's site or our recall page before you buy.12
  2. Scan for stored fault codes with a BMW-capable tool. A generic OBD reader misses most BMW modules. Specialist guides recommend a BMW-level scan (ISTA or similar) to catch faults that have been cleared from the dash but still stored.13,14
  3. Start it from cold. Ask the seller not to warm the car up first. Chain rattle, VANOS rattle, lifter tick and rough idle show most clearly in the first seconds after a cold start.13,15,16
  4. Ask a BMW dealer about warranty extensions and campaigns. Several BMW warranty extensions follow the car, not the owner, and some reimburse earlier repairs. A dealer can check the VIN. The list for this chassis is below.
  5. Get a pre-purchase inspection from a BMW specialist. A few hundred dollars for an independent BMW specialist is the usual advice, especially for M cars and high-mileage turbo engines.17,13
  6. Look for oil spots under the rear wheels. A sign of a rear differential leak.9
  7. Test iDrive, phone mirroring and the audio thoroughly. Connectivity and bass dropouts are the most common owner complaints.9

Engine items to listen and look for are in the known problems section.

Service-history red flags

  • Oil changes only at the long computer interval. Several guides advise changing oil more often than the onboard service indicator (CBS) suggests, especially with lots of city driving.16,18
  • Gaps in the records around known failure mileages. If the engine section below lists a job that usually comes due at the car's mileage, ask for the invoice. A missing record isn't proof it wasn't done, but it is a negotiating point.
  • Tuned or "deleted" cars. Tunes, emissions deletes and removed parts complicate warranty claims and inspections and raise wear on turbo cars. Ask, and look for aftermarket intakes, downpipes and charge pipes.
  • B46/B48: ask for records of Coolant leak at the oil filter housing; Brittle coolant hoses and couplings; Turbo oil return line leak (early cars); Fuel tank vent (purge) valve.
  • B58: ask for records of Coolant loss: oil filter housing, vent hose, water pump, expansion tank; Valve cover gasket and PCV; Fuel tank vent (purge) valve.

Which G20 to look for

330i or M340i. Both use the newer B-series engines. The M340i's B58 also has a 15 yr/150,000 mi extension on its tank vent valve and, on some cars, its PCV valve (see the engine section).

These are the views of the cited reviewers and specialists, not a ranking of our own.

G20 specs

BMW's US figures we have on file run from 255 hp (330i) to 382 hp (M340i), with 0-60 mph as quick as 4.2 s.

No manual gearbox appears in the EPA listings for this chassis. Full G20 specs: every US engine, transmission and drive by year →

Factory paint and option codes

Paint colors BMW of North America listed for the G20 in the ordering and pricing guides we read:

CodeColorModel years
300Alpine White2021
475Black Sapphire Metallic2021
668Jet Black2021
A75Melbourne Red Metallic2021
A83Glacier Silver Metallic2021
A96Mineral White Metallic2021
B39Mineral Grey Metallic2021
C10Mediterranean Blue Metallic2021
C1MPhytonic Blue Metallic2021
C1XSunset Orange Metallic2021
C31Portimao Blue Metallic2021
C35Blue Ridge Mountain Metallic2021
C36Dravit Grey Metallic2021
C3ZTanzanite Blue II Metallic2021

97 option codes are listed for the G20 in the same guides. Search them.

Only model years covered by the guides we could obtain are shown.

Coding

The coding apps' own lists show 173 settings that owners can change on the G20 with a phone and an OBD adapter, in areas such as Seat heating/cooling, Head-Up Display, Display options instrument cluster, Cleaning, Display options iDrive system, Comfort Functions. 118 come from BimmerCode's list and 55 more appear only in Carly's list.

Full G20 coding list with tool, difficulty and caveats →

Ownership costs

Routine maintenance: oil service prices by engine size, published BMW Value Service prices (brakes, spark plugs) from 16 US dealers, and the G20 maintenance schedule. Most G20 models: 4- and 6-cylinder $119.99 tier; M3 "Other".

Repairs we price that apply to the G20

Repair and owner-reported prices
B58 / B48 oil filter housing (coolant leak)
Owners paid: indie shop $1,800–$3,300 · dealer $2,825–$3,950
B58 valve cover / PCV failure
Owners paid: dealer $3,049–$4,450
B58 / B48 fuel tank vent valve (purge valve)
B58 coolant expansion tank (G05 X5 40i, high- or low-temp)
B58 heat management module (thermostat) replacement
B58 oil pump replacement
Owners paid: indie shop $2,865–$3,600
B58 water pump (coolant pump)
ZF 8-speed automatic transmission fluid and pan/filter service
B58 engine mounts (G-series)
Owners paid: indie shop $1,475–$2,575

"Owners paid" is the middle 50% of sourced owner prices across chassis with the same engine. Each job page reprices for your ZIP.

By model year

YearModels and enginesNHTSA recallsWarranty extensionsRepairs we price
2019330i / xDrive B46/B4811134
Priciest: B58 / B48 oil filter housing (coolant leak), owners paid up to $3,950 (dealer, middle 50%)
2020330i / xDrive B46/B48
M340i / xDrive B58		17129
Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%)
2021330i / xDrive B46/B48
330e / xDrive B46/B48 plug-in hybrid
M340i / xDrive B58		12119
Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%)
2022330i / xDrive B46/B48
330e / xDrive B46/B48 plug-in hybrid
M340i / xDrive B58		579
Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%)
2023330i / xDrive B46/B48
330e / xDrive B46/B48 plug-in hybrid
M340i / xDrive B58		349
Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%)
2024330i / xDrive B46/B48
330e / xDrive B46/B48 plug-in hybrid
M340i / xDrive B58		259
Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%)
2025330i / xDrive B46/B48
330e / xDrive B46/B48 plug-in hybrid
M340i / xDrive B58		129
Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%)
2026330i / xDrive B46/B48
330e / xDrive B46/B48 plug-in hybrid
M340i / xDrive B58		009
Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%)

Recalls and warranty extensions are counted when their published model-year range includes that year. Each one may cover only some cars, so check by VIN. Repairs counted are the ones whose engine was offered that year.

More for the G20

G20 repair costs and recalls G20 common problems G20 maintenance schedule Used BMW VIN check

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