



The 06K 121 143 aluminum coolant hose adapter by BG is a precision-machined, direct-fit upgrade that replaces the factory plastic adapter with durable aluminum construction for a reliable, leak-free seal under cooling system pressure.
$8.00
The 06K 121 143 aluminum coolant hose adapter by BG is an upgraded replacement fitting designed for select Volkswagen and Audi EA888 1.8T and 2.0T applications. Mounted in the cylinder head, this adapter serves as a critical junction in the engine cooling system, providing a secure connection between the coolant hose and the cylinder head coolant circuit to ensure proper coolant flow and system pressure retention. The aluminum construction offers improved resistance to heat cycling and cracking compared to the original plastic unit.
Factory plastic coolant hose adapters on EA888 engines are a well-known failure point. Constant heat cycling, vibration, and pressurized coolant exposure cause the plastic housing to become brittle, crack, or warp at the sealing surface — resulting in coolant seepage at the cylinder head area, low-coolant warnings, and potential engine overheating. Replacing the failed factory adapter with this BG aluminum 06K 121 143 unit restores a tight, leak-free seal and improves long-term durability over the original plastic design.
On EA888-equipped VW and Audi vehicles, a failing coolant hose adapter typically shows as coolant weeping or dried residue around the cylinder head in the area where the adapter mounts. A persistent coolant smell after driving, unexplained reservoir level drops, or a low-coolant warning are common indicators. Physical inspection may reveal a visibly cracked or brittle housing, especially around the hose barb or O-ring sealing bore. A fully failed adapter can result in sudden, significant coolant loss and engine overheating. Early replacement is strongly recommended to prevent escalating damage.
OEM Reference: 06K 121 143; supersedes 06K 121 143A, 06K 121 143B, 06K 121 143C
Brand: BG — OE-style replacement supplier
Aluminum construction for improved durability over the factory plastic unit
Precision-machined for correct hose alignment and factory-style fit at the cylinder head
Designed to maintain a tight, leak-free seal under cooling system pressure
Direct-fit replacement; no modifications required to the factory cooling system
Replace the O-ring and any associated seals and hose clamps during installation for a long-lasting, leak-free repair. Refill with the correct VW/Audi-approved coolant and properly bleed the cooling system after service. Inspect nearby coolant hoses and plastic fittings; replacing aging components together helps prevent repeat leaks.
Always verify fitment by VIN before ordering.
| Make | Model | Generation | Year Range | Engine |
|---|---|---|---|---|
| Volkswagen | Golf / GTI | Mk7 / Mk7.5 | 2015–2021 | 1.8T / 2.0T EA888 Gen3 |
| Volkswagen | Jetta | A6 / Mk6 | 2011–2018 | 1.8T / 2.0T EA888 Gen3 |
| Volkswagen | Passat | B7 / B8 | 2012–2019 | 1.8T / 2.0T EA888 Gen3 |
| Volkswagen | Tiguan | MQB | 2018–2024 | 2.0T EA888 Gen3 |
| Volkswagen | Atlas | MQB | 2018–2023 | 2.0T EA888 Gen3 |
| Audi | A3 | 8V | 2015–2020 | 1.8T / 2.0T EA888 Gen3 |
| Audi | Q3 | 8U | 2015–2018 | 2.0T EA888 Gen3 |
06K 121 143
06K 121 143A
06K 121 143B
06K 121 143C
| Weight | 0.35 lbs |
|---|---|
| Dimensions | 4.0 × 3.0 × 2.0 in |


The 06K 121 143 is an OE-spec coolant hose adapter for select Volkswagen and Audi EA888 1.8T and 2.0T applications. Precision-molded to factory specifications, this direct-fit replacement restores a factory-tight seal at critical coolant junctions — no modifications required. Includes O-ring.

The 03L 145 276 is an OE-quality accessory belt idler pulley for select Volkswagen and Audi 2.0 TDI applications. Built to factory dimensions with a sealed bearing, this direct-fit pulley restores correct belt alignment and quiet accessory drive operation — no modifications required.


The ABS Speed Sensor WHT003860 is a genuine-spec, OE-quality replacement for select Volkswagen and Audi models. It delivers precise wheel-speed data to your ABS, ESP, and traction control systems with a direct plug-and-play installation and no modifications required.


The Service Tech ABS Speed Sensor WHT003858 is a cost-effective, OE-style replacement for select Audi and Volkswagen models. It delivers accurate wheel-speed data to your ABS, ESP, and traction control systems — restoring full safety-system performance with a straightforward plug-and-play installation.


The Saleri Italo Water Pump 07K121011B is an OE-quality replacement for select Volkswagen engines. It restores reliable coolant circulation, keeps your engine at the correct operating temperature, and installs directly with no modifications required.