Water Pump and Thermostat Module in Uprated

A cooling part: the combined module on the later engines, where the pump and thermostat are one assembly and there is no choice in the matter.

We are an independent parts supplier. We are not Volkswagen, Audi, Seat or Skoda, and we are not appointed by any of them. Those are their trademarks and what we sell are parts that fit their cars. The useful thing about this group is that four badges share platforms and share parts, so the same component fits a Golf, an A3, a Leon and an Octavia and costs four different amounts at four different counters. We list it once, at one price, and tell you which platform it belongs to.

Specification and fitment

• Fits: Golf Mk5 Mk6 Mk7 Mk8, Passat B6 B7 B8, A3 8P 8V 8Y, A4 B8 B9, Leon 1P 5F KL, Octavia 1Z 5E NX, and the other group cars on the same platforms
• Platform: chosen above. This part is shared across the group. The Volkswagen, the Audi, the Seat and the Skoda all take it, it is the same component in four different boxes, and the price here is the same whichever badge is on your car. Choose your badge above for your records, not because it changes anything.
• Engine: 1.6 and 2.0 TDI, 1.4 1.8 and 2.0 TSI. This group changes specification mid production and does it on a platform basis rather than a model year basis, so two cars registered the same week can take different parts. Send us the VIN with the order and we check the part against the build data before anything is dispatched. It takes two minutes and it is the difference between a part that fits and a return.
• Production dates: 2003 to 2022 depending on platform
• Quality: the revised part number, which on this group matters more than on most. A great many of these components were superseded because the original failed, and the listing says exactly what changed and when
• Part number: cross referenced to the group part number for your VIN and confirmed before dispatch. We do not print one number against a listing that covers several supersessions, because on this group the supersessions are the whole point
• The failure this addresses: overheating at speed with a full expansion tank, a sweet smell, a low coolant warning that keeps coming back, a heater that blows cool at idle, or a white crust at a hose joint. Almost all of it is a plastic part doing a job that heat makes plastic bad at
• Labour time: one to five hours, and longer where the water pump is behind the timing belt, which on most of these it is
• Coding: no coding, but the adaptation channels should be reset with a diagnostic system afterwards or the car keeps running on values it learned from the failed part
• Also needed: coolant to the group specification, new O rings and hose clips, and a vacuum fill afterwards
• Torque: plastic housings are torqued low and in sequence. Overtightening one cracks it on the bench and the crack does not show until it is warm
• Interval: not scheduled, but if the water pump is behind the timing belt then its interval is the belt's, and that is the whole argument for doing them together. Do the water pump with the belt. It is driven by the belt, it is behind the same covers, it is a fraction of the parts cost and it is most of the labour. A water pump that fails eighteen months after a belt change means paying the belt labour again, and it is the commonest false economy in this shop.
• Weight: approximately 2.9 kilograms
• Warranty: three years or 36,000 miles, whichever comes first
• Belt driven pumps: on most of these engines the water pump is behind the timing belt. That makes it the same labour as the belt and makes doing them separately an expensive mistake
• Vacuum fill: fill under vacuum rather than pouring in. An air lock will cook a head gasket while the gauge reads normal, because the sender is measuring coolant and the trouble is air
• Metal impeller: this is the metal impeller version, which removes the failure rather than resetting its clock
• Coolant: the group specification must not be mixed with another. Mixed coolant gels and blocks the heater matrix, which is a dashboard out job

What arrives

• the part as described
• O rings, gaskets and clips
• coolant where the item includes it
• instructions with torque figures and the vacuum fill note

Fitting

One to five hours, and much longer if the pump is behind the timing belt, which on most of these it is. Fill under vacuum rather than pouring it in, because an air lock will destroy a head gasket while the temperature gauge sits happily in the middle.

Which version to buy

If the water pump is behind the timing belt, and on most of these engines it is, then the pump and the belt are one job and doing them separately means paying the labour twice. Beyond that the only decision is plastic or metal, and on a car you intend to keep the metal impeller costs a little more and removes the failure permanently.