BMW M240i Problems: 10 Issues Every Owner Should Know

2016-2024 model years · Based on 1,345+ owner reports · Last updated March 2026

According to Au7o's analysis of 1,345+ owner reports, the 2016-2024 BMW M240i has 10 documented known issues, with 3 rated critical by the Au7o research team. The most serious are Coolant Loss from Expansion Tank and Water Pump Failure ($400-$1,200 repair), N55 Rod Bearing Premature Wear - F87 M2 ($2,500-$4,500 repair) and S55 Crank Hub Failure (CATASTROPHIC) - M2 Competition ($1,200-$2,500 repair). The most commonly reported issue is Coolant Loss from Expansion Tank and Water Pump Failure with 420 owner reports. Across all issues, repair costs range from $150 to $8,000. Full technical analysis and DIY maintenance guides at au7o.io.

3
Critical
7
Moderate
0
Minor

All 10 Known Issues

Filter:

The N55 engine in the F87 M2 (2016-2018) suffers from accelerated rod bearing wear, though not as catastrophic as the S65 V10. Track use, aggressive driving, and extended oil change intervals accelerate bearing wear. Tight bearing clearances and high cylinder pressures in the M-tuned N55 contribute to the issue. Symptoms typically appear after 60,000-80,000 miles or after multiple track days. Unlike M3/M5, most M2 owners catch this before complete failure, but preventive replacement is strongly recommended for track-driven cars.

Common Symptoms

  • Metallic knocking noise at idle (especially when warm)
  • Oil pressure fluctuation or low oil pressure warning
  • Metal particles visible in oil (send oil sample to Blackstone Labs)
  • Engine noise increases with RPM
  • Low oil pressure at hot idle (below 14 PSI)

How to Fix

Preventive rod bearing replacement recommended at 60,000 miles or before track use. Upgraded aftermarket bearings (ACL Race, King Racing) provide larger clearances and better durability. Oil analysis every 5,000 miles to monitor bearing wear (check for copper/lead particles). Use high-quality 5W-40 oil (Liqui Moly, Motul) and change every 5,000 miles max for track cars. Some track-focused owners replace bearings every 50,000 miles preventively.

What Owners Are Using

Parts and tips from 0+ owners who fixed this issue

  • UpgradeACL Race bearings (6B1584H-STD) with increased clearances - most popular upgrade for track M2s. $170-187 for full set. (ACL #6B1584H-STD)
  • UpgradeKing Racing XP bearings (CR222SV) - another high-quality option with excellent track record. $30-35 per set x3 sets needed. (King Racing #CR222SV)
  • UpgradeLiqui Moly 5W-40 or Motul 8100 X-cess 5W-40 - excellent oil for high-performance N55 (Liqui Moly #2228)
  • TipSend oil samples to Blackstone Labs every 5k miles - early warning system for bearing wear
  • TipIf you track the car, replace bearings preventively at 50k-60k miles - don't wait for symptoms
  • NoteTrack use accelerates bearing wear dramatically - mandatory oil analysis if you track the M2
  • UpgradeBimmerWorld WPC-treated OEM rod bearings - factory bearings with WPC surface treatment for dramatically improved wear resistance. $552 per set. (BimmerWorld WPC-Treated OEM N55 Rod Bearings)
Typical repair cost:$2,500 - $4,500

Research This Issue

0+ owners have reported this issue

Medium Confidence0 reportsLast reported by owners Invalid DateReviewed Invalid Date

The M2 Competition shares the S55 engine with M3/M4 and inherits the catastrophic crank hub failure issue. The crank hub (harmonic balancer) is press-fit onto the crankshaft and can slip under high load, especially with upgraded software or track use. When the hub slips, timing is lost and valves contact pistons, destroying the engine. This is the same critical failure point as the F80 M3 and F82 M4. The OEM crank hub has inadequate interference fit. Most failures occur on tuned cars or during hard track use between 30,000-70,000 miles.

Common Symptoms

  • Sudden catastrophic engine failure with no warning
  • Rough idle or vibration (early warning if hub is starting to slip)
  • Check engine light with timing correlation codes (P0016, P0017)
  • Misfire codes across all cylinders
  • Metal-on-metal noise from front of engine

How to Fix

MANDATORY preventive replacement with upgraded pinned or keyed crank hub. Pure Turbos, VTT, and S55 Crank Hub Fix all sell upgraded solutions with mechanical retention (pin or keyway). Installation requires crankshaft pulley removal and careful torque specs. This is considered essential maintenance for any S55-powered car, especially if tuned or tracked. Many M2 Competition owners perform this upgrade immediately after purchase.

What Owners Are Using

Parts and tips from 0+ owners who fixed this issue

  • UpgradeSSR Performance crank hub fix (SSR-S55-CRANK) - mechanically pins hub to crankshaft, eliminating slip failure permanently. $949. (SSR Performance #SSR-S55-CRANK)
  • UpgradeBimmerWorld expanded S55 crank hub kit (100.11.680.0012) - comprehensive kit with all hardware and upgraded components. $1,599. (BimmerWorld #100.11.680.0012)
  • NoteDo NOT tune or track the car before upgrading the crank hub - you will grenade the engine
  • NoteThis is NOT optional for M2 Competition - it WILL fail eventually, especially if tuned
  • TipInstall upgraded crank hub before any performance mods - it's mandatory insurance for S55 engines
  • Upgrade034 Motorsport crank hub capture plate (034-113-Z016) - additional retention plate that prevents hub slip. $70, excellent cheap insurance alongside main crank hub fix. (034 Motorsport #034-113-Z016)
Typical repair cost:$1,200 - $2,500

Research This Issue

0+ owners have reported this issue

Medium Confidence0 reportsLast reported by owners Invalid DateReviewed Invalid Date
Community Reported
340 owners

The B58 engine uses a plastic charge pipe to route compressed air from the turbocharger to the throttle body. Under sustained high boost conditions, the factory plastic charge pipe can crack, split, or blow off, resulting in an immediate and total loss of boost pressure. This failure can occur on completely stock vehicles as the plastic degrades from repeated heat cycling over time, but is accelerated by any ECU tune that increases boost pressure.

Common Symptoms

  • Sudden and complete loss of boost pressure
  • Loud pop or hissing sound from engine bay
  • Check engine light with boost pressure codes
  • Significant power loss, especially above 3,000 RPM
  • Turbo whistle or whooshing noise under acceleration

How to Fix

Replace the factory plastic charge pipe with an upgraded aluminum aftermarket unit from manufacturers like Burger Motorsports, VRSF, or FTP Motorsport. If the failure occurs on a stock car, BMW may cover repair under warranty. After replacement, inspect the intercooler boots and all charge air connections for damage.

What Owners Are Using

Parts and tips from 340+ owners who fixed this issue

  • TipUpgrade to an aluminum charge pipe proactively - it's a $200-300 part and 1-hour install. Much cheaper than being stranded when the plastic one fails at 40k miles.
  • NoteIf you have any ECU tune increasing boost, consider the aluminum charge pipe mandatory. The stock plastic pipe is not rated for increased boost pressures.
Typical repair cost:$200 - $600

Research This Issue

340+ owners have reported this issue

High Confidence340 reportsLast reported by owners Invalid DateReviewed Mar 2026
Community Reported
310 owners

The B58 engine's valve cover gasket is prone to degradation and oil leaks, typically developing around 60,000-100,000 miles. The rubber gasket material shrinks and dries out through repeated heat cycles, allowing oil to seep and eventually drip down the sides of the engine. In more severe cases, oil can leak into the spark plug tubes, causing misfires and potential ignition coil damage.

Common Symptoms

  • Burning oil smell from engine bay, especially after highway driving
  • Visible oil seepage around valve cover edges
  • Oil dripping on exhaust manifold causing smoke
  • Oil pooling in spark plug wells causing misfires
  • Low oil level between changes

How to Fix

Replace the valve cover gasket with an updated BMW part. If oil has entered spark plug tubes, replace spark plugs and inspect ignition coils. Clean all oil residue from the engine block. Some owners replace the entire valve cover assembly as the integrated PCV valve can also fail.

What Owners Are Using

Parts and tips from 310+ owners who fixed this issue

  • TipWhen replacing the valve cover gasket, also replace the spark plug tube seals and inspect the PCV valve. It's all accessible at the same time and saves labor.
  • UpgradeUse the OEM Victor Reinz gasket set - aftermarket gaskets tend to shrink faster on turbocharged engines due to higher heat.
Typical repair cost:$500 - $900

Research This Issue

310+ owners have reported this issue

High Confidence310 reportsLast reported by owners Invalid DateReviewed Mar 2026
Community Reported
275 owners

The B58 engine's VANOS solenoid o-rings degrade due to wear and high temperatures, causing oil leaks and variable valve timing faults. When the o-rings fail, oil pressure to the VANOS system is compromised, leading to rough idle, reduced power, and check engine lights. This is a continuation of a problem that has affected multiple generations of BMW inline-6 engines.

Common Symptoms

  • Rough idle, especially when cold
  • Reduced power and acceleration hesitation
  • Check engine light with VANOS codes
  • Oil leak around VANOS solenoid area on top of engine
  • Engine stalling at low RPM

How to Fix

Replace the VANOS solenoid o-rings with updated silicone o-rings. Clean the solenoid screens of any debris. If solenoids are contaminated, replace the entire solenoid unit. Use BMW-approved 0W-30 oil and maintain proper oil change intervals to reduce o-ring degradation.

What Owners Are Using

Parts and tips from 275+ owners who fixed this issue

  • TipO-ring replacement is a DIY-friendly job. Buy a full o-ring kit from FCP Euro or ECS Tuning and replace all VANOS solenoid o-rings at once. Takes about 30 minutes with basic tools.
  • NoteDo not ignore VANOS codes - continued driving with failed o-rings can cause oil starvation to the VANOS unit, leading to much more expensive repairs.
Typical repair cost:$150 - $500

Research This Issue

275+ owners have reported this issue

High Confidence275 reportsLast reported by owners Invalid DateReviewed Mar 2026

Both the N55 (M2) and S55 (M2 Competition) engines use plastic charge pipes that fail under boost pressure and heat cycles. The charge pipe routes pressurized air from the turbocharger(s) to the engine intake. Plastic becomes brittle and cracks, especially on tuned cars running higher boost. Failure causes sudden loss of power and limp mode. The N55 has a single large charge pipe, while the S55 has multiple boost pipes that can fail. Aftermarket aluminum pipes are considered mandatory for any tuned M2.

Common Symptoms

  • Sudden loss of power while driving
  • Loud hissing or whooshing sound from engine bay
  • Check engine light with boost pressure codes (P0299, P0234)
  • Limp mode activation
  • Visible crack in plastic charge pipe
  • Boost gauge shows loss of pressure (if equipped)

How to Fix

Replace with upgraded aluminum charge pipe. Popular brands: ARM Motorsports, VRSF, BMS (Burger Motorsport). Aluminum pipes eliminate the plastic failure point permanently and support higher boost levels for tuned cars. Install is straightforward DIY. For M2 Competition, also consider upgrading all boost pipes while engine bay is accessible. Many M2 owners install aluminum charge pipes preventively before failure.

What Owners Are Using

Parts and tips from 0+ owners who fixed this issue

  • UpgradeARM Motorsports aluminum charge pipe for N55 M2 - perfect fit, supports 600+ HP, eliminates plastic failure. $200-300. (ARM Motorsports F87 M2 Aluminum Charge Pipe)
  • UpgradeVRSF charge pipe kit (10801050) for M2 Competition S55 - aluminum upgrade eliminates plastic failure permanently. $300. (VRSF #10801050)
  • TipInstall aluminum charge pipe BEFORE tuning - plastic pipes will fail immediately with more boost
  • TipFor M2 Competition, upgrade all boost pipes at once - save labor and prevent future failures
  • NoteIf you're running a tune without upgraded charge pipes, you're on borrowed time
Typical repair cost:$200 - $800

Research This Issue

0+ owners have reported this issue

Medium Confidence0 reportsLast reported by owners Invalid DateReviewed Invalid Date
Community Reported
420 owners

The B58 engine in the M240i is prone to coolant loss caused by cracks in the plastic coolant expansion tank and premature electric water pump failure. The thermoplastic expansion tank degrades under repeated heat cycles, and in turbocharged engines where under-hood temperatures run high, this aging process accelerates. The electric water pump can fail internally and leak coolant from the pump housing or seals, sometimes before 50,000 miles. A BMW TSB addresses the coolant vent line on the cylinder head that cannot handle excessive high temperatures over the lifetime of the part.

Common Symptoms

  • Coolant level dropping without visible external leak
  • Low coolant warning light on dashboard
  • Sweet smell from engine bay
  • Steam or coolant pooling under vehicle after parking
  • Engine overheating warning
  • Coolant residue on expansion tank or water pump housing

How to Fix

Replace the coolant expansion tank with an updated unit at first sign of cracking or weeping. Proactively replace the electric water pump before 60,000 miles. Replace the coolant vent line on the cylinder head per TSB. Inspect all plastic coolant components during every oil service. Consider upgrading to an aluminum expansion tank from aftermarket suppliers like Mishimoto.

What Owners Are Using

Parts and tips from 420+ owners who fixed this issue

  • NoteDo not ignore low coolant warnings - the B58 can overheat and warp the head quickly. Pull over and shut off immediately if temperature spikes.
  • TipKeep a gallon of BMW-approved coolant (blue) in the trunk. Check expansion tank level monthly and look for hairline cracks in the plastic during oil changes.
  • UpgradeFCP Euro stocks OEM Mahle water pumps and expansion tanks with a lifetime replacement guarantee - great for this known failure item.
Typical repair cost:$400 - $1,200

Research This Issue

420+ owners have reported this issue

High Confidence420 reportsLast reported by owners Invalid DateReviewed Mar 2026

The F87 M2 and M2 Competition have marginal cooling capacity for sustained track use. The small grilles and compact engine bay restrict airflow to the radiator, oil cooler, and intercooler. On track, oil temperatures commonly exceed 280°F and coolant temperatures spike, leading to heat soak and power loss. The M2 Competition with S55 engine runs even hotter. Extended track sessions can cause cooling system component failure or engine damage from overheating. This is well-documented on M2 track forums and affects all F87 M2 models when pushed hard.

Common Symptoms

  • Oil temperature exceeding 280°F during track sessions
  • Coolant temperature warning on track
  • Noticeable power loss after 3-4 hot laps (heat soak)
  • Limp mode activation from overheating
  • Intercooler heat soak (reduced power on turbocharged models)
  • Fan running constantly after track session

How to Fix

Install aftermarket cooling upgrades for track use: CSF radiator (higher core density), aftermarket oil cooler (Mishimoto, CSF), upgraded intercooler (Wagner, CSF), and coolant reroute kit. Remove kidney grille blockage for better airflow. Install oil temperature and pressure gauges to monitor. Limit track sessions to 15-20 minutes with cool-down laps. Many serious track M2 owners install full cooling system upgrades ($2,500-4,000 total). For street use, stock cooling is adequate.

What Owners Are Using

Parts and tips from 0+ owners who fixed this issue

  • UpgradeCSF auxiliary radiator (8258) - high-performance drop-in replacement for M2/M2C. $449 each. Essential for track use. (CSF #8258)
  • UpgradeMishimoto oil cooler kit - critical for keeping oil temps under 260°F on track (Mishimoto M2 Oil Cooler Kit)
  • UpgradeWagner Tuning intercooler - eliminates heat soak on turbo M2s during track use (Wagner M2 Competition Intercooler)
  • TipIf you track the M2, cooling upgrades are mandatory - the stock system can't handle sustained abuse
  • TipRemove kidney grille blockage and front tow hook cover for better airflow - free mod
  • NoteDon't ignore high oil temps (280°F+) - you'll cook rod bearings and destroy the engine
  • UpgradeCSF front-mount heat exchanger (FMHE) (8075) - dramatically improves charge air cooling for M2 Competition. $699. (CSF #8075)
  • UpgradeDinan heat exchanger (D780-0001A) - high-quality alternative to CSF, excellent cooling performance. $650-700. (Dinan #D780-0001A)
Typical repair cost:$2,500 - $5,000

Research This Issue

0+ owners have reported this issue

Medium Confidence0 reportsLast reported by owners Invalid DateReviewed Invalid Date

The Getrag DCT (dual-clutch transmission) in the M2 and M2 Competition experiences clutch pack wear from aggressive driving, launches, and track use. The DCT has two clutches (odd and even gears) that wear over time. Symptoms include shuddering during low-speed acceleration, rough shifting, and slipping under hard acceleration. Track use and repeated launch control engagements accelerate wear. DCT fluid degradation also contributes to poor shift quality. This transmission is shared with M3/M4 and has similar failure patterns.

Common Symptoms

  • Shuddering or judder when accelerating from a stop
  • Rough or harsh shifting between gears
  • Slipping sensation under hard acceleration
  • Burning smell from transmission
  • Check engine light with transmission codes
  • Clutch slip warnings on iDrive

How to Fix

Replace DCT clutch pack ($4,000-6,000 parts + labor). Change DCT fluid every 30,000 miles with BMW-approved fluid to extend clutch life. Avoid excessive launch control use. Transmission adaptation reset via BMW software often improves shift quality temporarily. Some performance shops offer upgraded clutch packs for track use. Extended warranty coverage highly recommended for DCT-equipped M2s.

What Owners Are Using

Parts and tips from 0+ owners who fixed this issue

  • UpgradeBMW OEM DCT clutch pack - expensive but necessary for proper function (BMW DCT Clutch Pack)
  • UpgradeBMW DCT fluid (83222413511) - change every 30k miles to extend clutch life (BMW #83222413511)
  • TipChange DCT fluid every 30k miles max - fluid degradation kills clutches faster than driving style
  • TipLimit launch control use to special occasions - it puts massive wear on clutch packs
  • NoteBudget $5k-8k for eventual DCT clutch replacement - it's not if, but when on high-mileage M2s
  • UpgradePentosin DCTF/FFL-4 dual-clutch transmission fluid - recommended replacement fluid for BMW DCT service. $38 per liter. (Pentosin DCTF/FFL-4 Dual-Clutch Fluid)
  • UpgradeBimmerWorld complete DCT service kit (101.28.680.0002) - includes fluid, filter, gaskets, and hardware. Same kit used for M3/M4/M5 DCT. $800. (BimmerWorld #101.28.680.0002)
Typical repair cost:$5,000 - $8,000

Research This Issue

0+ owners have reported this issue

Medium Confidence0 reportsLast reported by owners Invalid DateReviewed Invalid Date

Track-driven M2s (especially with sticky tires and aggressive alignment) can develop cracks in the rear subframe mounting points. The rear subframe holds the differential and rear suspension, and high lateral loads from track driving stress the mounting points. Cracks typically occur at the rear subframe-to-chassis connection points. This is most common on M2 Competition models with stickier tires and more power. Street-driven M2s rarely experience this issue. Symptoms include clunking from the rear, alignment going out of spec, and visible cracks during inspection.

Common Symptoms

  • Clunking or banging noise from rear suspension over bumps
  • Rear end feels loose or unstable
  • Alignment drifts out of spec frequently
  • Visible cracks in subframe mounting points (requires lift inspection)
  • Abnormal tire wear from shifting alignment

How to Fix

Reinforce rear subframe mounting points with weld-in reinforcement plates before cracks develop. Several companies (Vince Bar, BMW Performance Parts) sell subframe reinforcement kits. Installation requires welding and should be done by experienced chassis specialist. For already-cracked subframes, weld repair and reinforcement is required. Track M2 owners should inspect subframe regularly. This is considered preventive maintenance for serious track cars.

What Owners Are Using

Parts and tips from 0+ owners who fixed this issue

  • UpgradeVince Bar subframe reinforcement kit - proven solution to prevent cracking on track M2s (Vince Bar M2 Subframe Reinforcement)
  • TipIf you track the M2, reinforce the subframe BEFORE cracks develop - way cheaper than repair
  • TipInspect subframe mounting points after every track season - early detection prevents major damage
  • NoteCracked subframe can lead to catastrophic suspension failure - don't ignore clunking noises
Typical repair cost:$1,000 - $2,500

Research This Issue

0+ owners have reported this issue

Medium Confidence0 reportsLast reported by owners Invalid DateReviewed Invalid Date

Frequently Asked Questions

What are the most common BMW M240i problems?

According to Au7o's analysis of 1,345+ owner reports, the 2016-2024 BMW M240i has 10 documented issues. The most frequently reported are: Coolant Loss from Expansion Tank and Water Pump Failure, N55 Rod Bearing Premature Wear - F87 M2, S55 Crank Hub Failure (CATASTROPHIC) - M2 Competition. Of these, 3 are rated critical and should be addressed promptly.

Is the BMW M240i reliable?

The 2016-2024 BMW M240i has 10 known issues documented across 1,345+ owner reports. 3 issues are rated critical: Coolant Loss from Expansion Tank and Water Pump Failure and N55 Rod Bearing Premature Wear - F87 M2 and S55 Crank Hub Failure (CATASTROPHIC) - M2 Competition. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.

How much does it cost to fix common BMW M240i problems?

Repair costs for known BMW M240i issues range from $150 to $8,000, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Coolant Loss from Expansion Tank and Water Pump Failure, typically costs $400-$1,200 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.

What year BMW M240i is the most reliable?

Reliability varies across model years of the BMW M240i. Based on owner reports, issues are most commonly reported in earlier model years. Au7o recommends checking the specific known issues for your target year before purchasing, and having a pre-purchase inspection performed by a qualified mechanic. Our known issues database covers the 2016-2024 BMW M240i with 10 documented issues from 1,345+ owner reports.

Get DIY Repair Guides for Your BMW M240i

AI-powered step-by-step repair and maintenance guides tailored to your exact vehicle. Enter your year, make, and model to get started.

Get Started Free