Audi Coolant Reservoir / Tank / Bottle Cap 4M0121321R

OEM Part #: 4M0-121-321-R (4M0121321R)

This page covers one exact OEM part number. Every unit we stocked has sold.

This coolant reservoir cap (OEM Part Number 4M0121321R) is designed for Audi models, including the A4 Quattro, A4 allroad, A5 Quattro, A5 Sportback, Q5, and Q5 Sportback from 2020 to 2023, equipped with 2.0L L4 engines. Located on the coolant reservoir, it plays a crucial role in maintaining proper coolant pressure and preventing leaks. A common issue addressed by this part is a faulty cap that can lead to coolant loss or overheating. Also referred to as a radiator cap or reservoir cap, this component ensures optimal performance and efficiency in your vehicle's cooling system. Compatible with alternative part numbers 8K0129697, 8W0121405K, and others.

Specifications

Specifications for Coolant Reservoir / Tank / Bottle Cap 4M0121321R
Fits Vehicle ModelA4, A5, Q5, Q5 PHEV
Fits Vehicle MakeAudi
OEM Part No4M0-121-321-R (4M0121321R)
CategoryRadiator / Coolant

Compatible Vehicles

Fits 47 vehicle configurations across 1 make, 2017-2024.

Check your specific vehicle before ordering. This list shows year, make, and model. Some years have multiple trims or engines that use different parts, and individual listings may have additional fitment notes (e.g. “with sunroof only”). Review the full variant list below, or message us with your VIN and we’ll confirm the match.

Audi

  • A4 2017-2024 · 12 variants
  • A5 2017-2024 · 23 variants
  • Q5 2018-2024 · 7 variants 5 with notes
  • Q5 PHEV 2020-2024 · 5 variants 5 with notes
View all 47 vehicle configurations — 10 with fitment notes
Full vehicle fitment list for Coolant Reservoir / Tank / Bottle Cap 4M0121321R
Year Make Model Trim Engine Note
2017 Audi A4 Sedan 2.0L l4 Turbo
2017 Audi A4 Quattro Sedan 2.0L l4 Turbo
2017 Audi A5 Quattro Convertible 2.0L l4 Turbo
2017 Audi A5 Quattro Coupe 2.0L l4 Turbo
2018 Audi A4 Sedan 2.0L l4 Turbo
2018 Audi A4 Quattro Sedan 2.0L l4 Turbo
2018 Audi A5 Quattro Convertible 2.0L l4 Turbo
2018 Audi A5 Quattro Coupe 2.0L l4 Turbo
2018 Audi A5 Hatchback 2.0L l4 Turbo
2018 Audi Q5 SUV 2.0L l4 Turbo
2019 Audi A4 Sedan 2.0L l4 Turbo
2019 Audi A4 Quattro Sedan 2.0L l4 Turbo
2019 Audi A5 Quattro Convertible 2.0L l4 Turbo
2019 Audi A5 Quattro Coupe 2.0L l4 Turbo
2019 Audi A5 Hatchback 2.0L l4 Turbo
2019 Audi Q5 SUV 2.0L l4 Turbo
2020 Audi A4 Sedan 2.0L l4 Turbo
2020 Audi A4 Quattro Sedan 2.0L l4 Turbo
2020 Audi A5 Quattro Convertible 2.0L l4 Turbo
2020 Audi A5 Quattro Coupe 2.0L l4 Turbo
2020 Audi A5 Hatchback 2.0L l4 Turbo
2020 Audi Q5 SUV 2.0L l4 Turbo For Vehicles with Production Date After 08/17/20
2020 Audi Q5 PHEV SUV 2.0L l4 Turbo For Vehicles with Production Date After 08/17/20
2021 Audi A4 Quattro Sedan 2.0L l4 Turbo
2021 Audi A5 Quattro Convertible 2.0L l4 Turbo
2021 Audi A5 Quattro Coupe 2.0L l4 Turbo
2021 Audi A5 Hatchback 2.0L l4 Turbo
2021 Audi Q5 SUV 2.0L l4 Turbo For Vehicles with Production Date After 08/17/20
2021 Audi Q5 PHEV SUV 2.0L l4 Turbo For Vehicles with Production Date After 08/17/20
2022 Audi A4 Quattro Sedan 2.0L l4 Turbo
2022 Audi A5 Quattro Convertible 2.0L l4 Turbo
2022 Audi A5 Quattro Coupe 2.0L l4 Turbo
2022 Audi A5 Hatchback 2.0L l4 Turbo
2022 Audi Q5 SUV 2.0L l4 Turbo For Vehicles with Production Date After 08/17/20
2022 Audi Q5 PHEV SUV 2.0L l4 Turbo For Vehicles with Production Date After 08/17/20
2023 Audi A4 Quattro Sedan 2.0L l4 Turbo
2023 Audi A5 Quattro Convertible 2.0L l4 Turbo
2023 Audi A5 Quattro Coupe 2.0L l4 Turbo
2023 Audi A5 Hatchback 2.0L l4 Turbo
2023 Audi Q5 SUV 2.0L l4 Turbo For Vehicles with Production Date After 08/17/20
2023 Audi Q5 PHEV SUV 2.0L l4 Turbo For Vehicles with Production Date After 08/17/20
2024 Audi A4 Quattro Sedan 2.0L l4 Turbo
2024 Audi A5 Quattro Convertible 2.0L l4 Turbo
2024 Audi A5 Quattro Coupe 2.0L l4 Turbo
2024 Audi A5 Hatchback 2.0L l4 Turbo
2024 Audi Q5 SUV 2.0L l4 Turbo For Vehicles with Production Date After 08/17/20
2024 Audi Q5 PHEV SUV 2.0L l4 Turbo For Vehicles with Production Date After 08/17/20

Ask a parts specialist

Asking about: Coolant Reservoir / Tank / Bottle Cap 4M0121321R · OEM #4M0121321R