MajorCommonCooling

Porsche Boxster: Water Pump Plastic Impeller Failure (987 Boxster)

Water Pump Plastic Impeller Failure (987 Boxster) is a common cooling fault on the Porsche Boxster on the 2005–2012 cars, and we rate it major. Putting it right costs $900 to $2,500 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 5 documented faults on the Porsche Boxster.

Vehicle: Porsche Boxster
Years: 2005–2012
Fuel: petrol
System: Cooling

This page covers the Porsche Boxster as a model. Some faults only affect particular engines or build years — enter a plate below to narrow the list to one car.

All Porsche Boxster faults5 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph of the Water pump yet. We would rather show none than show a picture of a different part.

What goes wrong

The 987 Boxster water pump uses a plastic impeller that is known to delaminate and spin free of its shaft. When the impeller disengages, coolant circulation stops but the pump appears externally intact, making diagnosis non-obvious. The engine overheats without any external coolant leak. Replacement with an all-metal impeller upgrade is the documented permanent fix and is recommended on any 987 without confirmed pump replacement history.

What you would notice

Engine overheating without any visible external coolant leak
Temperature gauge rising above the normal operating range
Coolant not circulating — return hose from radiator stays cold when engine is warm
Heater output reduced or absent at low speed

How to check it

Where to look. Water pump on the mid-mounted M97 engine, accessory belt driven

Check coolant hose temperatures with the engine warm — a cold return hose indicates circulation failure.
Ask whether the water pump has been replaced with a metal impeller unit.
Inspect service records for any overheating history.
Check coolant for discolouration, which can indicate impeller material breakdown in the system.

Parts involved: Water pump.

What it costs to put right

$900 to $2,500 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

Ask the seller

“Has the water pump been replaced, and was it upgraded to a metal impeller unit?”
“Has the car ever overheated or shown a high temperature warning?”
“What is the coolant service history including flush intervals?”

Now check the Porsche Boxster you are actually looking at

Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.

Not sure what you would be paying for? See what a full KickTyres check includes.

Where this comes from

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.

Porsche Boxster buyer questions

Is water pump plastic impeller failure (987 boxster) serious on a Porsche Boxster?

We rate it major and common on the Porsche Boxster. The 987 Boxster water pump uses a plastic impeller that is known to delaminate and spin free of its shaft. When the impeller disengages, coolant circulation stops but the pump appears externally intact, making diagnosis non-obvious. The engine overheats without any external coolant leak. Replacement with an all-metal impeller upgrade is the documented permanent fix and is recommended on any 987 without confirmed pump replacement history.

How much does it cost to fix on a Porsche Boxster?

$900 to $2,500 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.

Which Porsche Boxster years are affected?

Our research records this fault on the 2005–2012 Porsche Boxster. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.

How do I check for it before I buy?

Check coolant hose temperatures with the engine warm — a cold return hose indicates circulation failure. Ask whether the water pump has been replaced with a metal impeller unit. Inspect service records for any overheating history. Check coolant for discolouration, which can indicate impeller material breakdown in the system. Look here: Water pump on the mid-mounted M97 engine, accessory belt driven