Common Porsche Boxster and Cayman Problems by Generation
The common Porsche Boxster and Cayman problems depend on the generation. The 986 Boxster and the 987.1 Boxster and Cayman use M96 and M97 engines, with their known IMS bearing, bore scoring, rear main seal and air-oil separator issues. From the 987.2 onwards those engine concerns largely fall away, leaving the problems every Boxster and Cayman shares: clogged front radiators, roof and drain trouble on Boxsters, and suspension wear.
In short: The Porsche Boxster and Cayman have been built in four generations: the 986 Boxster (1996 to 2004), the 987 (2005 to 2012), the 981 (2012 to 2016) and the 718 (from 2016). The 986 and 987.1 have M96 or M97 engines with an IMS bearing and a risk of bore scoring. Later cars avoid those issues, and their common problems are cooling, roof, suspension and maintenance items.
How do the Boxster and Cayman generations compare?
The Boxster arrived in 1996, and the Cayman, its fixed-roof coupé sibling, joined it with the 987. The engine in each generation decides which problems matter most.
| Generation | Built | Engines | Issues most worth knowing |
|---|---|---|---|
| 986 Boxster | 1996 to 2004 | 2.5 litre, then 2.7 litre from 2000; Boxster S (from 2000) 3.2 litre. M96 family | IMS bearing, bore scoring, rear main seal, air-oil separator, coolant tank, roof |
| 987.1 Boxster and Cayman | 2005 to 2008 | Boxster 2.7; Boxster S 3.2, then 3.4 from model year 2007; Cayman 2.7 (from 2006); Cayman S 3.4. M96/M97 family | IMS bearing, bore scoring, rear main seal, air-oil separator |
| 987.2 Boxster and Cayman | 2009 to 2012 | Boxster and Cayman 2.9; S models 3.4 with direct injection; Boxster Spyder and Cayman R 3.4. 9A1 family | No IMS bearing; PDK maintenance; general wear |
| 981 Boxster and Cayman | 2012 to 2016 | 2.7 litre; S and GTS 3.4 litre; Boxster Spyder and Cayman GT4 3.8 litre | No IMS bearing; electric steering and parking brake; general wear |
| 718 Boxster and Cayman (982) | From 2016 | Mostly 2.0 and 2.5 litre turbocharged flat-fours; GTS 4.0, Spyder and Cayman GT4 models 4.0 litre flat-six | Turbo components on four-cylinder cars; general wear |
What are the common problems on the 986 Boxster?
The 986 Boxster’s common problems centre on its M96 engine: IMS bearing wear, bore scoring, rear main seal leaks and air-oil separator failure. Every 986 is now over 20 years old, so cooling, roof and suspension wear matter too.
IMS bearing and bore scoring
Every 986 engine has an intermediate shaft running on a sealed bearing, and if that bearing fails the engine can be badly damaged. The type of bearing makes a big difference to whether replacing it makes sense; our article on when to replace the IMS bearing sets out the options, and our IMS bearing replacement page explains the work. Bore scoring, wear to the cylinder walls, is the other well-known M96 concern, covered in our bore scoring guide.
Oil leaks, smoke and coolant
A light oil weep where the engine meets the gearbox is often the rear main seal. It’s rarely urgent, and the seal is usually renewed during a clutch change. A big cloud of smoke on start-up or a rough idle points towards the air-oil separator (AOS), a routine repair, but smoke can also be a sign of bore scoring, so it needs diagnosing. The plastic coolant expansion tank can crack with age, so look for coolant traces and a falling level.
Roof
Earlier 986s have a plastic rear window in the roof, which can discolour or split. Cars from the 2002 facelift have a heated glass window instead.
What are the common problems on the 987 Boxster and Cayman?
The 987’s common problems depend on whether it’s a 987.1 (2005 to 2008) or a 987.2 (2009 to 2012), because the two phases use different engine designs.
The 987.1 uses M96 and M97 engines, so the IMS bearing, bore scoring, rear main seal and air-oil separator all apply, as on the 986. On most 987.1 engines built from 2006, the larger IMS bearing can’t be replaced through the gearbox opening without major engine work, so regular oil changes and watching for warning signs are the practical approach.
The 987.2 moved to the 9A1 engine, which has no intermediate shaft and so no IMS bearing, and bore scoring is much less common on it. It also replaced the Tiptronic S automatic with the seven-speed PDK. Our guide to buying a used 987 Boxster or Cayman covers both phases in more detail.
What are the common problems on the 981 Boxster and Cayman?
The 981 isn’t known for a major engine weakness, so its common problems are the wear and maintenance items any sports car of ten years or more needs: radiators, suspension, brakes and PDK oil changes.
The 981 was the first Boxster and Cayman with electric power steering and an electric parking brake. Neither has a reputation for trouble, but on a used car check for warning messages and that the parking brake engages and releases cleanly. Like the 987.2, the 981 has no IMS bearing.
What should you know about the 718’s engines?
Most 718 Boxsters and Caymans use turbocharged four-cylinder engines: a 2.0 litre flat-four in the base and T models, and a 2.5 litre flat-four in the S models and the earlier GTS. The GTS 4.0, introduced in 2020, and the Spyder and Cayman GT4 models use a naturally aspirated 4.0 litre flat-six.
The four-cylinder engines have no IMS bearing, but turbocharging adds a turbocharger and boost pipework to check. A PIWIS diagnostic read-out and a road test under load are the best way to confirm all is well. Beyond that, service history and normal wear matter most.
Which problems affect every Boxster and Cayman?
Some problems apply to every generation, because they come from the layout of the car rather than its engine.
Front radiators clogging
Every Boxster and Cayman has its radiators at the front, behind the bumper openings. Leaves and road grit collect around the radiators and air-conditioning condensers, hold moisture against the fins and corrode them, which reduces cooling and can lead to leaks. Cleaning them thoroughly usually means taking the front bumper off, and it’s worth doing as routine maintenance.
Roof and drains on Boxsters
A Boxster’s fabric roof should open and close smoothly, with no torn seams or tired seals. Drains around the roof area carry rainwater away, and when leaves block them, water can get into the cabin, soaking the carpets and reaching electrical parts. On a Cayman, check that the tailgate opens, stays up and seals properly.
Suspension, brakes and tyres
Drop links, bushes, top mounts and dampers wear with age and mileage, and coil springs can break. Knocks over bumps, vague steering and uneven tyre wear are the usual signs. When parts are needed, we talk owners through the choice of Porsche Genuine, OE and aftermarket parts, but Lawrence only fits parts he knows and trusts.
Clutch and gearbox
Manual cars wear their clutches like any other, and a missed downshift can over-rev the engine; our guide to Porsche over-revs explains what the engine management records. PDK cars need their gearbox oil changed when Porsche’s schedule calls for it, as our PDK maintenance guide explains.
What should you check before buying a Boxster or Cayman?
Before buying any Boxster or Cayman, confirm which generation and engine it has, look for a full service history and have a specialist inspect it.
- History: servicing to Porsche’s schedule, with invoices. Evidence of IMS bearing, radiator or suspension work is a good sign, not a warning.
- Engine: a cold start with no smoke or unusual ticking. On an M96 or M97 engine, an endoscope inspection settles any doubt about bore scoring.
- Roof or tailgate: a full roof cycle on a Boxster, and dry carpets and luggage areas.
A Porsche pre-purchase inspection covers every aspect of the car. The car comes to our workshop in High Wycombe for it, as Lawrence doesn’t do mobile or on-site inspections.
Common questions
Which Boxster and Cayman models have an IMS bearing?
The 986 Boxster and the 987.1 Boxster and Cayman, built up to 2008, have an IMS bearing because they use M96 and M97 engines. The 987.2 from 2009, the 981 and the 718 don’t. On most 987.1 engines built from 2006, the bearing can’t be replaced without major engine work.
Which Porsche 718 models have a six-cylinder engine?
The 718 GTS 4.0, introduced in 2020, and the 718 Spyder and Cayman GT4 models use a naturally aspirated 4.0 litre flat-six. The 718 Boxster, Cayman, T and S models, and the earlier 718 GTS, use turbocharged four-cylinder engines of 2.0 or 2.5 litres.
Is a 986 Boxster still worth buying?
Yes, if its history is good and its engine checks out. A well-maintained 986 is still an enjoyable sports car, but at over 20 years old it needs buying on condition. Ask what has been done about the IMS bearing, look for evidence of cooling and suspension work, and have the engine checked for bore scoring before you commit.
Looking after your Boxster or Cayman
We look after every generation of Boxster and Cayman, from the 986 to the 718, at our workshop in High Wycombe. Lawrence has over 40 years with Porsche, and we service to Porsche’s schedules with PIWIS 4 diagnostics, extra preventative checks and a detailed inspection report. Read more on our Boxster and Cayman specialist page, book a pre-purchase inspection, call 01494 534834 or see our contact details.
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