BMW 4 Series known issues by generation

By CarWhere Research · Updated

The 4 Series split off from the 3 Series in 2014 as the coupe, convertible and Gran Coupe line, so the first-generation F32 shares most of its mechanical issues with the F30. The second-generation G22 is newer and so far its record consists mainly of recalls. 5 documented issues, 4 with NHTSA recall numbers.

CarWhere lists 5 documented 4 Series issues, including 4 NHTSA safety recalls, each with affected years, engines, symptoms, pre-purchase checks and a source.

4 Series generations at a glance

BMW 4 Series chassis codes and the known issues listed for each
Chassis codeModel yearsIssues on this page
F322014–2020 (F32/F33/F36)N20 / N26 timing-chain guide failure (class-action extended warranty) · Electric coolant pump connector can short (fire risk) · Head (curtain) airbag inflator weld may fail
G222021–present (G22/G23/G26)Cylinder head cover may crack and leak oil (2024 430i Convertible) · Starter relay can corrode and overheat

F32 4 Series problems (2014–2020)

N20 / N26 timing-chain guide failure (class-action extended warranty) (2014–2015)

Major repair
Chassis:
F32/F33/F36 428i
Years:
2014–2015
Engine:
N20 / N26 2.0L turbo inline-4

The 2.0-liter turbo four BMW introduced in 2012 used plastic timing-chain guides that, on early engines, could turn brittle and break apart; debris can then let the chain skip or snap and damage the engine. A second chain driving the oil pump was also alleged to stretch. Owners sued in New Jersey federal court (Gelis v. BMW), and the 2021 settlement kept BMW's 2017 7-year/70,000-mile chain extension and added sliding-scale coverage up to 8 years or 100,000 miles. Covered models included 2014–2015 428i alongside the 320i, 328i, 528i, X1, X3, X4, 228i and Z4 four-cylinder models. Revised parts went into production in 2015, and most cars have now aged out of the extension.

Symptoms

  • Whining or rattling from the front of the engine, especially on cold starts
  • Timing or camshaft-position fault codes
  • Sudden loss of power or engine stall if the chain fails

Check before buying

  • Ask for records showing the timing-chain module was replaced with the revised parts
  • Listen for chain whine at cold start and between 1,500–3,000 rpm
  • Check the engine build date; engines built after early 2015 use updated parts

Sources: [1][2][3][4]

Electric coolant pump connector can short (fire risk) (2014–2016)

Safety recall
Chassis:
F32/F33/F36 428i (shared with F30 328i and others)
Years:
2014–2016
Engine:
N20 2.0L turbo inline-4

BMW recalled four-cylinder turbo models because the electrical connector on the electric water pump may not be sealed well enough to keep water out. Moisture can short the connector, and the recall notes this raises the risk of a fire. Affected models include 2014–2016 428i and 428i xDrive, the 2015–2016 428i xDrive Gran Coupe, plus 3 Series, 5 Series, X1, X3, X4 and 2 Series cars. The dealer remedy is free.

Symptoms

  • Coolant-temperature or water-pump warnings
  • Burning or electrical smell from the engine bay

Check before buying

  • Enter the VIN at nhtsa.gov/recalls or ask a BMW dealer to confirm the recall work was completed
  • Look for a recent water-pump replacement on the invoice history

NHTSA recall: 24V-608 (2024-08) · 720,796 vehicles

Sources: [5]

Head (curtain) airbag inflator weld may fail (2014–2015)

Safety recall
Chassis:
F32/F36 (also F30 3 Series and F22 2 Series)
Years:
2014–2015
Engine:
N20 2.0L turbo inline-4; N55 3.0L turbo inline-6; S55 (M4)

The side head airbag inflator in 2014–2015 4 Series coupes and Gran Coupes, along with related 3 Series and 2 Series cars, can fail at a weld. Gas may leak out, leaving the airbag weak, or the inflator can rupture and throw fragments. BMW issued an additional campaign for 2014 cars in late 2025 (25V-871). The remedy is new inflators.

Symptoms

  • No warning signs before a crash

Check before buying

  • Enter the VIN at nhtsa.gov/recalls or ask a BMW dealer to confirm the recall work was completed
  • Check both 24V-288 and 25V-871 against the VIN

NHTSA recall: 24V-288 (2024-04) · 5,761 vehicles

Sources: [6][7]

G22 4 Series problems (2021–present)

Cylinder head cover may crack and leak oil (2024 430i Convertible) (2024)

Safety recall
Chassis:
G22/G23 (G23 430i Convertible)
Years:
2024
Engine:
B46 / B48 2.0L turbo inline-4

A group of 2024 430i convertibles was recalled because the plastic cylinder head (valve) cover can crack. Oil leaking onto hot engine or exhaust parts can catch fire. The fix is a replacement cover.

Symptoms

  • Oil smell or smoke from the engine bay
  • Oil drips under the front of the car

Check before buying

  • Enter the VIN at nhtsa.gov/recalls or ask a BMW dealer to confirm the recall work was completed
  • Look for oil residue around the top of the engine

NHTSA recall: 23V-863 (2023-12) · 5 vehicles

Sources: [8]

Starter relay can corrode and overheat (2021–2022)

Safety recall
Chassis:
G22/G23 430i (also G20, G30, G01, G02, G29)
Years:
2021–2022
Engine:
B46 / B48 2.0L turbo inline-4

2021–2022 430i coupes and convertibles are in the same starter-relay recall as other four-cylinder BMWs of the period. Corrosion can make the relay overheat and short, raising the risk of a fire. A separate 2026 campaign (26V-056) replaces starters on 2021–2024 4 Series cars that may overheat and catch fire from internal wear.

Symptoms

  • Intermittent no-start
  • Burning smell near the starter

Check before buying

  • Enter the VIN at nhtsa.gov/recalls or ask a BMW dealer to confirm the recall work was completed
  • Check 25V-636 and 26V-056 against the VIN

NHTSA recall: 25V-636 (2025-09) · 199,674 vehicles

Sources: [9][10]

Related 4 Series research

This page explains specific mechanical issues and recalls. Which model years drew the most owner complaints is a different question, answered in the years-to-avoid research from NHTSA complaint and service-bulletin counts.

Confirm exactly how a 4 Series was built before you buy.

Engine, gearbox and factory options decide which of these issues apply. The CarWhere build sheet decodes a BMW 4 Series VIN into its factory record — option codes, paint, upholstery and equipment as built. $9.99, instant.

BMW build sheet by VIN

Frequently asked questions

What are the most common BMW 4 Series problems?

The best-documented BMW 4 Series issues are N20 / N26 timing-chain guide failure (class-action extended warranty) (F32/F33/F36 428i, 2014–2015). How much each matters depends on the chassis code and engine, so check the section for the exact car you are looking at.

Which 4 Series years are affected by N20 / N26 timing-chain guide failure (class-action extended warranty)?

N20 / N26 timing-chain guide failure (class-action extended warranty) applies to F32/F33/F36 428i cars (2014–2015, N20 / N26 2.0L turbo inline-4). The 2.0-liter turbo four BMW introduced in 2012 used plastic timing-chain guides that, on early engines, could turn brittle and break apart; debris can then let the chain skip or snap and damage the engine.

Has the BMW 4 Series had any safety recalls?

Yes. Recalls covered on this page include electric coolant pump connector can short (fire risk) (NHTSA 24V-608), head (curtain) airbag inflator weld may fail (NHTSA 24V-288), cylinder head cover may crack and leak oil (2024 430i Convertible) (NHTSA 23V-863) and starter relay can corrode and overheat (NHTSA 25V-636). Recall repairs are free at a BMW dealer; check any specific car’s VIN with NHTSA to see whether its recall work was completed.

What should I check before buying a used BMW 4 Series?

Ask for records showing the timing-chain module was replaced with the revised parts. A pre-purchase inspection by a BMW specialist covers these and pulls the service history.

Is the BMW 4 Series reliable?

Most well-known BMW 4 Series problems are tied to specific chassis codes or engines rather than the model as a whole, and many have a known fix or updated part.

Sources

Issue descriptions are CarWhere’s own summaries of the sources below. Chassis codes covered: F32 (2014–2020 (F32/F33/F36)), G22 (2021–present (G22/G23/G26)). Repair costs are shown only where a source states them and vary by shop and region.

  1. BMW Timing Chain Lawsuit Settlement Final — CarComplaints.com
  2. BMW Timing Chain Lawsuit Settlement Reached — CarComplaints.com
  3. BMW Class Action Seeks Fix for Engine Chain Defect — Top Class Actions
  4. How BMW Replaced One Of Its Best Engines With One Of Its Worst Engines — The Autopian
  5. NHTSA Recall 24V-608: Electric water pump connector short circuit — NHTSA
  6. NHTSA Recall 24V-288: Head air bag inflator may fail at weld joint — NHTSA
  7. NHTSA Recall 25V-871: Head air bag inflator issue (2014 2/3/4 Series) — NHTSA
  8. NHTSA Recall 23V-863: Cylinder head cover may crack and leak oil — NHTSA
  9. NHTSA Recall 25V-636: Engine starter relay may corrode and short circuit — NHTSA
  10. NHTSA Recall 26V-056: Starter assembly recall (2021–2024 4 Series and others) — NHTSA

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Independent reference compiled by CarWhere — not affiliated with or endorsed by BMW AG or BMW of North America. BMW, M and the model names are trademarks of their owner.