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BMW G29 Z4 buyer's guide
2019–present · sDrive30i, M40i (B46/B48, B58)
Last updated
Engines by year Model-year changes Known problems Warranty extensions Recalls Inspection checklist Red flags Specs Paint codes Coding Ownership costs Sources
Models and engines by year
US-market models. Chassis codes: G29. Not sure which one you have? The VIN check decodes year, model and engine.
Model-year changes
| Model year | What changed |
|---|---|
| Launch | Introduced at Pebble Beach on 23 August 2018 for the 2019 model year; developed alongside the Toyota Supra.8 |
| 2019 | US lineup in the EPA listings: 2.0L 4-cyl turbo: Z4 sDrive30i.9 |
| 2020 | New: Z4 M40i (3.0L 6-cyl turbo).9 |
| Facelift (LCI) | The LCI model was introduced in September 2022.8 |
| 2025 | Manual gearbox now listed: Z4 M40i.9 |
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
sDrive30i (2019–present) · B46/B48 bulletins
| Problem | When it shows up | What to know | Repair prices |
|---|---|---|---|
| Coolant leak at the oil filter housing | most reports about 60,000–80,000 miles | BMW 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 G60.1,2,3 | B58 / B48 oil filter housing (coolant leak) Owners paid: indie shop $1,800–$3,300 · dealer $2,825–$3,950 |
| Brittle coolant hoses and couplings | age and heat related | Plastic connectors near hot parts crack and can burst.3,2 | No price yet |
| Turbo oil return line leak (early cars) | early production | Caused by a mis-assembled gasket, fixed under warranty on early engines.3 | No price yet |
| Fuel tank vent (purge) valve | any mileage | Evap 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).4 | B58 / B48 fuel tank vent valve (purge valve) |
B58 engine
M40i (2019–present) · B58 bulletins
| Problem | When it shows up | What to know | Repair prices |
|---|---|---|---|
| Coolant loss: oil filter housing, vent hose, water pump, expansion tank | commonly from about 60,000–80,000 miles; water pumps typically last about 75,000–100,000 | Often 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.5,2,6 | B58 / B48 oil filter housing (coolant leak) Owners paid: indie shop $1,800–$3,300 · dealer $2,825–$3,950 |
| Valve cover gasket and PCV | valve cover gaskets about 60,000–100,000 miles | Oil 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).7,5 | B58 valve cover / PCV failure Owners paid: dealer $3,049–$4,450 |
| Fuel tank vent (purge) valve | any mileage | Evap 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).4 | B58 / B48 fuel tank vent valve (purge valve) |
Warranty extensions and service campaigns 1
Warranty extensions (1)
- SIB 01 03 24 EVAP system warranty extension EVAP system warranty extension on BMW G01/G02/G05/G06 and other models (2017–2025); BMW extended the warranty on this part for eligible cars. Warranty extension · Jun 2026
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 12
- 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 23V821: integrated transmission control unit 4 SERIES, 8 SERIES, X3, X4, X5, X6, Z4, 2023. The weld seam of the integrated transmission control unit's cover may not have been manufactured properly, which could allow automatic transmission oil to leak into the transmission control unit.
- Recall 23V099: digital key ECU software coding 230I, 840I, M2, M240I, M8, M850I, Z4, 2022–2023. BMW of North Americal, LLC (BMW) is recalling certain 2023 8 Series Coupe (840i, 840i xDrive, M850i xDrive, M8), 8 Series Convertible (840i, 840i xDrive, M850i xDrive, M8), 8 Series Gran Coupe (840i, 840i xDrive, M850i xDrive, M8, Alpine B8 xDrive), 2 Series Coupe (230i, 230i xDrive, M240i xDrive, M
- 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.
- Recall 20V700: fuel tank Z4, 2020–2021. The weld between the fuel tank halves may have been insufficiently welded, causing the weld to fail.
- Recall 20V516: headlamp adjustment plug Z4, 2019–2020. The headlamps are able to be adjusted horizontally.
- Recall 20V355: steering gear tie rod 330I, M340I, X3, X4, Z4, 2019–2020. In certain driving conditions, such as high temperatures and rough road surfaces, a steering gear tie rod may become damaged, possibly resulting in a fractured tie rod.
- Recall 19V850: headlights 330I, Z4, 2020. The headlight control units may fail causing a loss of one or both of the headlights.
- Recall 19V732: engine 330I, Z4, 2019–2020. The needle roller bearings of the counterbalance shafts may have been improperly installed, potentially causing the counterbalance shaft to loosen.
- Recall 19V684: camera 330I, 530E, 530I, 540D, 540I, 640I, 740LE, 740LI, 745LE, 750LI, 840I, M340I, M5, M550I, M850I, X3, X4, X5, X6, X7, Z4, 2018–2020. The back-up camera and display settings can be adjusted such that the rear view image is no longer visible and the system will retain that setting the next time the vehicle is placed in reverse.
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
- 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.10
- 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.11,12
- 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.11,13,14
- 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.
- 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.15,11
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.14,16
- 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.
G29 specs
BMW's US figures we have on file run from 255 hp (Z4 sDrive30i) to 382 hp (Z4 M40i), with 0-60 mph as quick as 3.9 s.
A manual gearbox was offered in model years 2025–2026 (EPA listings). Full G29 specs: every US engine, transmission and drive by year →
Factory paint and option codes
Paint colors BMW of North America listed for the G29 in the ordering and pricing guides we read:
| Code | Color | Model years |
|---|---|---|
| 300 | Alpine White | 2021, 2026 |
| 475 | Black Sapphire Metallic | 2021, 2026 |
| A83 | Glacier Silver Metallic | 2021 |
| A96 | Mineral White Metallic | 2021 |
| C10 | Mediterranean Blue Metallic | 2021 |
| C1D | Misano Blue Metallic | 2021 |
| C34 | San Francisco Red Metallic | 2021, 2026 |
| C37 | Frozen Grey II Metallic | 2021, 2026 |
| C31 | Portimao Blue Metallic | 2026 |
| C4E | San Remo Green Metallic | 2026 |
| C4W | Skyscraper Grey Metallic | 2026 |
| C56 | Thundernight Metallic | 2026 |
| C7L | Frozen Deep Green Metallic | 2026 |
103 option codes are listed for the G29 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 149 settings that owners can change on the G29 with a phone and an OBD adapter, in areas such as Seat heating/cooling, Head-Up Display, Cleaning, Comfort Functions, Display options instrument cluster, Display options iDrive system. 85 come from BimmerCode's list and 64 more appear only in Carly's list.
Ownership costs
Routine maintenance: oil service prices by engine size, published BMW Value Service prices (brakes, spark plugs) from 16 US dealers, and the G29 maintenance schedule.
Repairs we price that apply to the G29
| 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) |
"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
| Year | Models and engines | NHTSA recalls | Warranty extensions | Repairs we price |
|---|---|---|---|---|
| 2019 | sDrive30i B46/B48 M40i B58 | 6 | 1 | 7 Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%) |
| 2020 | sDrive30i B46/B48 M40i B58 | 8 | 1 | 7 Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%) |
| 2021 | sDrive30i B46/B48 M40i B58 | 5 | 1 | 7 Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%) |
| 2022 | sDrive30i B46/B48 M40i B58 | 3 | 1 | 7 Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%) |
| 2023 | sDrive30i B46/B48 M40i B58 | 3 | 1 | 7 Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%) |
| 2024 | sDrive30i B46/B48 M40i B58 | 1 | 1 | 7 Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%) |
| 2025 | sDrive30i B46/B48 M40i B58 | 0 | 1 | 7 Priciest: B58 valve cover / PCV failure, owners paid up to $4,450 (dealer, middle 50%) |
| 2026 | sDrive30i B46/B48 M40i B58 | 0 | 0 | 7 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.
Sources
- BMW SIB 11 10 25: coolant leaking from oil filter housing (B46/B48), via NHTSA
- Motronix: B46/B58 coolant leaks at the oil filter housing
- Bimmerly: B48 reliability
- BMW SIB 01 02 24: EVAP purge valve warranty extension (BimmerBench summary)
- BMWTuning: 5 most common B58 problems
- r/F30: high-mileage B58 coolant and OFH issues
- R44 Performance: B58 engine review
- Wikipedia: BMW Z4 (G29)
- EPA/DOE fuel economy data (fueleconomy.gov)
- NHTSA recall lookup by VIN
- The Stable: E92 M3 buyer's guide
- Euro Premium Parts: E60 M5 reliability guide
- carsales: buying a used F30 3 Series (2015–20)
- carsales: buying a used E90 3 Series
- Road & Track: E46 M3 buyer's guide
- Drive-My: E60 5 Series buying guide (six-cylinder petrol)
Retrieved 2026-10-18. Bulletins and recalls come from NHTSA filings; owner prices come from the public posts linked on each job page.