Also known as: m96, m97, 3.4 flat-six, 3.6 flat-six, ims, 996 engine, boxster engine
Porsche's first water-cooled flat-six — the engine of the 996 and 997 911 and of the Boxster and Cayman of that era, and the design that ended thirty years of air cooling.
It is defined by the intermediate shaft bearing, universally known as the IMS. The bearing supports a shaft that drives the camshaft chains; when it fails, debris circulates and the engine is generally destroyed. Failure rates were low in absolute terms but the consequence is total, the bearing design changed several times across production, and whether a given car's bearing has been replaced is the single most valuable piece of history about it. Later engines moved to a non-serviceable design.
Bore scoring on the larger-displacement versions is the second theme, presenting as ticking and oil consumption. Both faults are internal, both are expensive, and both mean an oil analysis and a filter inspection are worth far more on this engine than a scan tool is.
Cars fitted with this engine
3 generations, across 1 make. From the authored catalogue — an absent car means the catalogue has not reached it, not that the engine was never fitted.
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Posted about this engine
Be the first to write this up
Nothing posted about this yet. Whatever you found is worth writing down — even a dead end saves someone the same afternoon.
What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
- What actually fixed it — or that nothing did, which is worth knowing too.
Sign in or create an account to add what you found about M96 / M97.