2017-2021 Audi / Porsche Coolant Reservoir / Tank / Bottle Cap 4M0121321J

OEM Part #: 4M0-121-321-J (4M0121321J)

$19.99
Used
Donor2017 Audi Q7 · 3.0L
SKU: 704908 · 30-Day Returns
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Coolant Reservoir / Tank / Bottle Cap 4M0121321J — Used (SKU 704908)
Genuine OEM Used SKU: 704908 Donor Vehicle: 2017 Audi Q7 · 3.0L 2 photos
$19.99
30-Day Returns
  • Genuine OEM — real photos
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A used genuine OEM Audi Coolant Reservoir / Tank / Bottle Cap, part number 4M0121321J, also replaces 4M0121321E. This cap seals the expansion tank on multiple Audi and Porsche models with 2.0L turbocharged, 2.9L, 3.0L, and 3.0L supercharged engines. A failing cap can allow coolant to leak or prevent proper system pressure, leading to overheating.

Specifications

Specifications for Coolant Reservoir / Tank / Bottle Cap 4M0121321J
Fits Vehicle ModelA4, A5, Macan, Q5, Q7
Fits Vehicle MakeAudi, Porsche
OEM Part No4M0-121-321-J (4M0121321J)
Compatible OEM Part No 4M0-121-321-E
CategoryRadiator / Coolant

Compatible Vehicles

Fits 36 vehicle configurations across 2 makes, 2017-2021.

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 2017-2021 · 9 variants 9 with notes
  • A5 2017-2021 · 14 variants 14 with notes
  • Q5 2018 1 with note
  • Q7 2017 · 2 variants 2 with notes

Porsche

  • Macan 2019-2021 · 10 variants 10 with notes
View all 36 vehicle configurations — 36 with fitment notes
Full vehicle fitment list for Coolant Reservoir / Tank / Bottle Cap 4M0121321J
Year Make Model Trim Engine Note
2020 Porsche Macan S SUV 3.0L V6 Turbo For Vehicles With Production date Up To 08/31/20
2020 Porsche Macan GTS SUV 2.9L V6 Turbo For Vehicles With Production date Up To 08/31/20
2021 Porsche Macan S SUV 3.0L V6 Turbo For Vehicles With Production date Up To 08/31/20
2020 Porsche Macan Turbo SUV 2.9L V6 Turbo For Vehicles With Production date Up To 08/31/20
2020 Porsche Macan SUV 2.0L l4 Turbo For Vehicles With Production date Up To 08/31/20
2021 Porsche Macan GTS SUV 2.9L V6 Turbo For Vehicles With Production date Up To 08/31/20
2021 Porsche Macan SUV 2.0L l4 Turbo For Vehicles With Production date Up To 08/31/20
2021 Porsche Macan Turbo SUV 2.9L V6 Turbo For Vehicles With Production date Up To 08/31/20
2019 Porsche Macan S SUV 3.0L V6 Turbo For Vehicles With Production date Up To 08/31/20
2019 Porsche Macan SUV 2.0L l4 Turbo For Vehicles With Production date Up To 08/31/20
2019 Audi A4 Quattro Sedan 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2019 Audi A4 Sedan 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2018 Audi A5 Quattro Coupe 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2018 Audi A5 Hatchback 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2018 Audi A5 Quattro Convertible 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2019 Audi A5 Quattro Convertible 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2019 Audi A5 Hatchback 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2021 Audi A5 Quattro Convertible 2.0L l4 Turbo For Vehicles With Production date Up To 06/15/20
2020 Audi A5 Quattro Convertible 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2020 Audi A4 Quattro Sedan 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2017 Audi A5 Quattro Convertible 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2017 Audi A4 Sedan 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2017 Audi A5 Quattro Coupe 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2017 Audi Q7 SUV 3.0L V6 Supercharged For Vehicles With Production date Up To 11/21/16
2017 Audi A4 Quattro Sedan 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2018 Audi A4 Sedan 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2018 Audi A4 Quattro Sedan 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2017 Audi Q7 SUV 2.0L l4 Turbo For Vehicles With Production date Up To 11/21/16
2018 Audi Q5 SUV 2.0L l4 Turbo For Vehicles With Production date Up To 03/27/17
2020 Audi A5 Quattro Coupe 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2021 Audi A5 Quattro Coupe 2.0L l4 Turbo For Vehicles With Production date Up To 06/15/20
2020 Audi A4 Sedan 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2021 Audi A4 Quattro Sedan 2.0L l4 Turbo For Vehicles With Production date Up To 06/15/20
2021 Audi A5 Hatchback 2.0L l4 Turbo For Vehicles With Production date Up To 06/15/20
2020 Audi A5 Hatchback 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19
2019 Audi A5 Quattro Coupe 2.0L l4 Turbo For Vehicles With Production date Up To 06/17/19

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