About this part
The 06M121013G water pump kit is the brand new genuine OEM cooling pump conversion set for the EA839 turbo V6 family — the 3.0 TFSI in the Audi S4, S5, SQ5, A6, A7, A8, Q7 and Q8, and the 2.9 TFSI biturbo in the RS4, RS5, S6 and S7. Volkswagen Group redesigned the pump at the pulley flange: the earlier 4-bolt pump (06M121013C, then 06M121013D) is no longer supported, and every replacement now uses the stronger 6-bolt flange. Because the bolt pattern changed, the pump cannot be fitted under the old 4-bolt pulley — the 6-bolt 06M121031G pulley and six new N91121903 bolts must go on with it, and that is exactly what this kit supplies: one water pump with its gasket, one 06M121031G pulley and six N91121903 pulley bolts. It is a brand new, genuine quality set, ready to fit, for workshops and owners facing a weep-hole leak, bearing play or a squealing pump on a 3.0 TFSI or 2.9 TFSI engine.
water pump kit — genuine 06M121013G 6-bolt water pump with gasket, 06M121031G pulley and six N91121903 bolts for the Audi / VW EA839 3.0 TFSI and 2.9 TFSI turbo V6; direct conversion replacement for 06M121013C and 06M121013D.
OE/OEM Part Number:
06M121013G, 06M121013C, 06M121013D, 06M121031G, 06M121031D, N91121903
What the pump does, and why it fails
The coolant workhorse of a hot V6. The EA839 sits its turbocharger inside the V of the engine, where heat soaks everything around it, and the water pump keeps coolant moving through the block, the heads and the charge cooling circuit from start-up to full load. Driven by the serpentine belt through the pulley on the pump nose, it runs every minute the engine runs, in coolant that is routinely above 100 °C.
Failure mode one: the shaft seal and weep hole. The ceramic seal faces wear with age, heat cycles and coolant condition, and the first sign is usually a pink or green crust below the weep hole on the pump housing — coolant escaping slowly, then faster. Left alone, the level drops, the engine runs hot, and on a turbo V6 that has no spare thermal margin, cylinder-head gasket damage follows quickly.
Failure mode two: bearing play. The pump bearing carries the belt load at several thousand rpm. Coolant that was topped up with hard tap water, or left beyond its service life, corrodes the bearing races. Play at the pulley, a whine or squeak that changes with engine speed, and in the worst cases a pulley that wobbles enough to throw the belt are all late stages of the same wear. A thrown serpentine belt on these engines also disables the alternator and the power steering, so the car stops with more than a leak.
Why the kit exists: the 4-to-6-bolt changeover. Volkswagen Group phased out the 4-bolt pump during the 06M121013D era and moved production and spares to the 6-bolt flange of the 06M121013G. The old 06M121031D pulley does not line up with the new flange, and stretching the old pulley bolts across the new pattern is not an option — the flange cracks. Every pump replacement on these engines is now a conversion job, needing the pump, the 06M121031G pulley and six N91121903 bolts, and the earlier 4-bolt hardware (pulley 06M121031D, bolts N10832501) is retired with it. Ordering the pump alone and reusing the old pulley is the single most common mistake on this job; this kit removes it.
Symptoms, diagnosis and installation
• Typical symptoms — dried coolant crust or an active drip below the pump weep hole, a slow coolant loss with no visible puddle, a whine or squeak from the front of the engine that tracks rpm, visible wobble at the pump pulley with the engine idling, a thrown serpentine belt, and on RS models under sustained load, high coolant temperature warnings.
• Confirm it before ordering — with the belt off, rock the pump pulley by hand: any radial play or a rough feel when spinning it means the bearing is done. Check the weep hole for fresh or dried coolant traces. Look at the old pump flange and count the bolt holes: four holes means the car still wears the old pulley and needs this full conversion kit; six holes means the conversion is already done and the kit still fits as a like-for-like replacement. If in doubt, send us a photo of the old pump before ordering.
• Installation notes — drain the coolant down to below the pump level and let the engine cool before starting. Remove the serpentine belt from the pump pulley, unbolt the old pump, and clean both mating faces on the block — old gasket residue is the most common cause of a leak after the job. Fit the supplied gasket dry, torque the pump bolts evenly to the published figure, then mount the 06M121031G pulley with the six new N91121903 bolts — they are one-time stretch bolts, so never reuse the old ones. Refill with the specified G12 class coolant and bleed the system per the workshop procedure, then run to temperature and re-check the level and the weep hole.
• Fitment caution — the kit fits the EA839 turbo V6 petrol engines by engine code, not by model badge: 3.0 TFSI CWGD (S4, S5, SQ5), DLZA (A6, A7), CZSE (A8), DCBD (Q7, Q8) and 2.9 TFSI DECA / DECC (RS4, RS5), DKMB (S6, S7). It does not fit the older EA837 3.0 TFSI supercharged V6, the 4.2 FSI V8, or the Porsche versions of the EA839, which use their own part set. Confirm the engine code on the vehicle sticker or by VIN before ordering.
Fitment
This kit covers the whole EA839 turbo V6 petrol family by engine code: the 3.0 TFSI single-turbo in the B9 S4 and S5, the SQ5, and the 55 TFSI versions of the A6, A7, A8, Q7 and Q8; and the 2.9 TFSI biturbo in the RS4, RS5, S6 and S7. Whether the car left the factory on the 4-bolt or the 6-bolt pump, this is the current genuine service set for both. The table below lists the usual applications; confirm the engine code against the vehicle before ordering.
| Make | Model | Years | Engine |
|---|---|---|---|
| Audi | S4 B9 (8W) | 2017 – 2024 | 3.0 TFSI — CWGD |
| Audi | S5 B9 (8W / F5) | 2017 – 2024 | 3.0 TFSI — CWGD |
| Audi | SQ5 FY | 2017 – 2024 | 3.0 TFSI — CWGD |
| Audi | A6 C8 / A7 C8 55 TFSI | 2019 – 2024 | 3.0 TFSI — DLZA |
| Audi | A8 D5 55 TFSI | 2019 – 2024 | 3.0 TFSI — CZSE |
| Audi | Q7 4M / Q8 55 TFSI | 2019 – 2024 | 3.0 TFSI — DCBD |
| Audi | RS4 B9 / RS5 (F5) | 2017 – 2024 | 2.9 TFSI — DECA, DECC |
| Audi | S6 C8 / S7 C8 | 2020 – 2024 | 2.9 TFSI — DKMB |
Shipping and packing
Orders leave within one to two working days of cleared payment, packed in a foam-lined box with the pump, the pulley and the bolt bag protected separately so the gasket faces, the pulley groove and the bolt threads arrive undamaged. Tracking is emailed when the parcel is handed to the carrier. Customs charges, where they apply, are the buyer’s responsibility.
Condition & warranty
Brand new genuine quality 06M121013G water pump kit — pump with gasket, 06M121031G pulley and six N91121903 bolts — twelve months warranty against manufacturing defects covering the kit as supplied. The warranty does not cover damage from coolant contamination or wrong-spec coolant, from reuse of the old stretch bolts or pulley, or from incorrect installation torque. If a part arrives faulty, send us photos before returning anything.
Wholesale
Tiered pricing for 1 pc, 5 pcs and 20 pcs is shown below. Workshops and resellers servicing EA839 engines should ask for a combined quote — we price mixed orders of water pump kits, thermostats, coolant pipes and seals together, and these engines often need more than the pump alone when the cooling system is opened.
