Heating and Cooling› Thermostats, Housings and Fillers

Racingline

MQB Coolant Expansion Tank Cap

$12.95

SKU: 2Q0121321A

In Stock
In Stock
Ships by Sep 9
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Beginner — under 30 min

Overview

The VAG MQB Coolant Expansion Tank Cap is a direct replacement part for your vehicle's coolant system. It features an ergonomic grip for easier removal and installation.
Show original supplier description
This cap is crucial for sealing the coolant reservoir, which holds excess engine coolant and is responsible for maintaining optimal pressure within your vehicle's cooling system. It is a newer design found on MQB MK7.5 Golf/GTI models and is compatible with all VAG vehicles from 1996 onwards. This cap offers enhanced functionality with its ergonomic grip, making it easier to remove and install when refilling your coolant bottle. This upgraded design not only contributes to a cleaner appearance in the engine bay but also improves user convenience. The cap is constructed from plastic and has a pressure rating of 1.6 bar. This part is confirmed to fit a wide range of Audi and other VAG models, including numerous A1, A3, Q2, and Q3 variants, among others, from 1996 to the present. Please verify fitment for your specific vehicle year, model, and engine.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandRacingline
Part Number2Q0121321A
CategoryHeating and Cooling

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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