The 2021 Morgan Plus Six uses BMW's B58 3.0L turbo inline-six and ZF 8HP transmission in a hand-built aluminum chassis. It's mechanically robust but suffers from bespoke British build quality issues, electrical gremlins, and serviceability nightmares due to tight packaging and coach-built construction.
Transmission Mount and Cooler Line Failures
Common · medium severityTypical onset: 15,000-35,000 mi
Symptoms: Clunking during shifts or acceleration, Transmission fluid leaks at cooler lines or fittings, Vibration at idle that worsens under load, Transmission overheating warnings on spirited drives
Fix: Morgan's custom transmission installation uses modified mounts and cooler routing that don't handle vibration well. Mounts crack early; cooler lines chafe against frame rails. Replacement requires chassis access panels removal, custom fabrication sometimes needed. 4-6 hours labor for mounts, 3-4 hours for cooler lines.
Estimated cost: $1,200-2,800
Engine Bay Fuse Box Water Intrusion
Common · high severitySymptoms: Random electrical faults after rain or car wash, Check engine light with multiple stored codes, Intermittent no-start or crank-no-start, Headlights, fuel pump, or ignition cutting out randomly, Corrosion visible in fuse box terminals
Fix: The engine bay fuse box sits low and forward with inadequate weatherproofing—water enters through bonnet gaps. Requires fuse box replacement, harness terminal cleaning/repair, and aftermarket sealing modifications. Diagnosis 2-3 hours, repair 4-6 hours depending on corrosion extent. Many owners add custom splash shields.
Estimated cost: $1,800-4,200
LED Headlight Module Failures
Occasional · medium severitySymptoms: One or both headlights flickering or going dark, Headlight error messages on startup, Intermittent operation when hitting bumps, Moisture visible inside headlight housing
Fix: Morgan uses semi-custom LED assemblies with poor vibration isolation and seal quality. Modules fail from road shock; housings leak. Entire assembly replacement required—no individual module service. Parts are special-order from UK, 4-8 week lead times common. 2-3 hours labor per side including aim.
Estimated cost: $2,200-3,800
Cylinder Head Gasket and Cooling System Issues
Rare · high severityTypical onset: 40,000-70,000 mi
Symptoms: White smoke from exhaust on cold start, Coolant loss with no visible leaks, Oil cap shows milky residue, Overheating under sustained load, Rough idle with misfires on cylinders 1-3
Fix: BMW B58 is generally solid, but Morgan's tight engine bay causes cooling issues—inadequate airflow leads to head gasket stress. If caught early, resurfacing saves the head. Engine removal required due to chassis design (no top access). 18-24 hours labor for head gasket job with R&R. If head is warped, add machine shop time and another 3-5 hours install.
Estimated cost: $6,500-11,000
Fuel Filter and Pump Access Nightmares
Occasional · low severityTypical onset: 30,000-50,000 mi
Symptoms: Hard starting when fuel tank below 1/4, Loss of power under acceleration, Engine stumbling or cutting out at highway speed, Fuel pressure fault codes
Fix: Fuel filter is a scheduled 30k service item but requires partial interior removal and custom panel access—Morgan buried it. Pump replacement means tank drop, which involves removing rear suspension components. What should be a 1-hour filter job takes 3-4 hours. Pump replacement 6-8 hours. Use OEM BMW parts only.
Estimated cost: $450-800 filter, $2,000-3,200 pump
Check Engine Light - Evaporative Emissions and Fuel System Codes
Common · low severitySymptoms: P0442, P0455, P0456 evap leak codes, P0087 fuel rail pressure too low, CEL illuminates after refueling, Fuel smell near filler area, Failed emissions testing in strict states
Fix: Morgan's custom fuel tank and evap system uses mismatched BMW parts with hand-fabricated lines—leak points everywhere. Purge valves, vent valves, and filler neck seals fail regularly. Diagnosis requires smoke test, 1-2 hours. Repairs range from simple valve replacement (1 hour) to tank seal work (4-6 hours with rear suspension disassembly).
Estimated cost: $300-1,800
Buy only if you have deep pockets for specialist labor and tolerance for electrical quirks—it's a BMW drivetrain wrapped in artisanal British complexity, and you pay for both sides of that equation.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.