The 2021 718 Cayman S with the 2.5L turbocharged flat-four is still relatively new, but early patterns show the turbocharged four-cylinder platforms can suffer from catastrophic bearing failures and piston/cylinder scoring under hard use—issues that plagued earlier 981/982 generation engines and persist in some units.
Catastrophic Engine Bearing Failure (IMS-era Successor Problem)
Occasional · high severityTypical onset: 20,000-60,000 mi
Symptoms: metallic knocking or rattling from engine at idle or under load, sudden loss of oil pressure warning, engine seizure without warning, metal debris visible in oil during changes
Fix: Complete engine teardown reveals spun rod or main bearings, typically requiring full short block replacement or engine rebuild with new bearings, pistons, and crankshaft. 25-35 labor hours for short block R&R, more if machine work needed. Porsche has issued quiet service campaigns on some VINs but not an official recall.
Estimated cost: $15,000-25,000
Piston/Cylinder Bore Scoring
Occasional · high severityTypical onset: 30,000-70,000 mi
Symptoms: blue smoke on cold start that clears after warmup, excessive oil consumption (more than 1 qt per 1,000 mi), rough idle when engine is cold, loss of compression evident in performance hesitation
Fix: Borescope inspection confirms vertical scoring in cylinder walls. Requires cylinder sleeve replacement or complete short block replacement, new pistons and rings minimum. 30-40 labor hours. Some cases covered under extended Porsche warranty if documented early.
Estimated cost: $12,000-22,000
Transmission Oil Cooler Leaks
Common · medium severityTypical onset: 40,000-80,000 mi
Symptoms: transmission fluid spots under car near front or mid-section, low transmission fluid warnings on dash, burnt smell after spirited driving, visible seepage around cooler lines
Fix: Cooler line o-rings or cooler itself develops leaks due to heat cycling. Requires undercar access, draining PDK fluid, replacing cooler and/or lines. 4-6 labor hours including fluid refill and system bleed.
Estimated cost: $1,200-2,200
Transmission Mount Failure (PDK)
Occasional · medium severityTypical onset: 50,000-90,000 mi
Symptoms: clunking when shifting from reverse to drive or vice versa, excessive drivetrain movement felt through cabin during hard acceleration, vibration at idle in gear, visible cracking or separation in rubber mount
Fix: PDK transmission mount rubber deteriorates from heat and stress. Requires transmission support, removal of old mount, installation of updated mount. 3-4 labor hours.
Estimated cost: $800-1,400
Fuel Filter Clogging (Track/High-Performance Use)
Rare · medium severitySymptoms: fuel starvation during hard cornering or sustained high-g maneuvers, stumbling or cutting out at high RPM under load, check engine light with fuel pressure fault codes, loss of power above 5,000 RPM
Fix: In-tank fuel filter becomes restricted, especially in cars used on track with older fuel or debris in tank. Requires fuel tank drop, filter replacement, tank cleaning. 5-7 labor hours.
Estimated cost: $1,000-1,800
Head Gasket Failure (Post-Bearing Damage)
Rare · high severitySymptoms: coolant mixing with oil (milky oil cap residue), white smoke from exhaust, overheating without external leaks, bubbles in coolant reservoir
Fix: Usually secondary to overheating event or bearing failure aftermath. Requires cylinder head removal, deck surface inspection/machining, new gaskets, studs. 18-24 labor hours per bank if caught early; often becomes full rebuild scenario.
Estimated cost: $8,000-14,000
I'd buy one with a CPO warranty or extensive documentation of clean oil analysis and borescope inspections—otherwise, you're gambling on a $20K engine time bomb that can detonate without warning.
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.