Shop Our Clearance Sale - Up To 80% Off FREE SHIPPING on Orders $49+ *exclusions apply

Menu

Call Us330-331-2003 ChatLive Chat Text Us!
0 Shopping Cart
Your Vehicle

No Vehicle selected
Please select your vehicle below.

    • Audi
    • BMW
    • Mercedes Benz
    • MINI
    • Porsche
    • Volkswagen

Saved Vehicles

My Vehicles
You currently have no stored vehicles.

Recent Vehicles

Recent Vehicles Manage Vehicles

You currently have no recent vehicles.

We'll automatically keep fully selected vehicles here for your convenience.

Call Us330-331-2003 ChatLive Chat Text Us!
Track My Order View Order History Submit a Return Contact Us Wholesale Information Lifetime Replacement Returns and Warranty Information
0
Call Us330-331-2003 ChatLive Chat Text Us!
Track My Order View Order History Submit a Return Contact Us Wholesale Information Lifetime Replacement Returns and Warranty Information
Cancel
0
Sales & Specials
Enter Your Vehicle
garage-red
Your Vehicle Please tap 'Select' to pick a vehicle
Your Vehicle Please tap 'Select' to pick a vehicle
Select

Audi B7 Coolant Expansion Tank Caps

Sort By
Filter By
Return to Top

Porsche 911 Expansion Tank Cap

ES#3496004 - 99110645702 - Porsche 911 Expansion Tank Cap - Black and satin aluminum colored coolant cap from the Porsche 991. - Genuine Porsche - Audi Volkswagen Porsche

Black and satin aluminum colored coolant cap from the Porsche 991. affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
Genuine Porsche - Corporate Logo
ES#:
3496004
Mfg#:
99110645702
In Stock
$53.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Audi R8 Expansion Tank Cap

ES#4691207 - 420121321 - Audi R8 Expansion Tank Cap - Keep proper pressure on your coolant, replaces any modern blue or black cooling cap - Bremmen Parts - Audi Volkswagen Porsche

Keep proper pressure on your coolant, replaces any modern blue or black cooling cap affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms 10X Entries For Our 25th Anniversary Sweepstakes!

Brand:
Bremmen Parts - Corporate Logo
ES#:
4691207
Mfg#:
420121321
In Stock
ON SALE! SAVE 14%
$34.99

This product was last offered at the strikethrough price on
05-02-2026

$29.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Expansion Tank Cap

ES#253082 - 3B0121321 - Expansion Tank Cap - Keep proper pressure in your coolant system - Genuine Volkswagen Audi - Audi Volkswagen

Keep proper pressure in your coolant system affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
253082
Mfg#:
3B0121321
In Stock
25% off MSRP

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$39.59

This product was last offered at the strikethrough price on
01-08-2026

$29.67 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

CTS Coolant Tank Cap

ES#4620720 - CTS-ACC-009 - CTS Coolant Tank Cap - Lose the plastic! - CTS - Audi Volkswagen

Lose the plastic! affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
CTS - Corporate Logo
ES#:
4620720
Mfg#:
CTS-ACC-009
In Stock
$69.99 USD
Free Shipping
This product is lifetime replacement eligible Lifetime Replacement

Coolant Expansion Tank Cap

ES#3485290 - 2Q0121321A - Coolant Expansion Tank Cap - Keep proper pressure in your coolant system - Genuine Volkswagen Audi - Audi Volkswagen Porsche

Keep proper pressure in your coolant system affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
3485290
Mfg#:
2Q0121321A
In Stock
2% off MSRP

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$42.99

This product was last offered at the strikethrough price on
02-26-2026

$41.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Expansion Tank Cap

ES#10026 - 3B0121321 - Expansion Tank Cap - Keep proper pressure in your coolant system - Vaico - Audi Volkswagen Porsche

Keep proper pressure in your coolant system affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
We Price Match - Give Us A Call or Chat!

Brand:
Vaico - Corporate Logo
ES#:
10026
Mfg#:
3B0121321
In Stock
$15.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Audi R8 Expansion Tank Cap

ES#2149010 - 420121321 - Audi R8 Expansion Tank Cap - Keep proper pressure on your coolant, replaces any modern blue or black cooling cap - Genuine Volkswagen Audi - Audi Volkswagen Porsche

Keep proper pressure on your coolant, replaces any modern blue or black cooling cap affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
2149010
Mfg#:
420121321
Ships in 3 Business Days
9% off MSRP

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$326.99

This product was last offered at the strikethrough price on
02-26-2026

$298.99 USD
Free Shipping
This product is lifetime replacement eligible Lifetime Replacement

Coolant Expansion Tank Cap

ES#4858532 - 2Q0121321A - Coolant Expansion Tank Cap - Keep proper pressure in your coolant system - Bremmen Parts - Audi Volkswagen Porsche

Keep proper pressure in your coolant system affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms 10X Entries For Our 25th Anniversary Sweepstakes!

Brand:
Bremmen Parts - Corporate Logo
ES#:
4858532
Mfg#:
2Q0121321A
In Stock
ON SALE! SAVE 22%
$19.99

This product was last offered at the strikethrough price on
05-02-2026

$15.50 USD
Free Shipping
on orders $49 and up

Expansion Tank Cap

ES#2709040 - 3B0121321 - Expansion Tank Cap - Keep proper pressure in your coolant system - URO - Audi Volkswagen

Keep proper pressure in your coolant system affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
We Price Match - Give Us A Call or Chat!

Brand:
URO - Corporate Logo
ES#:
2709040
Mfg#:
3B0121321
In Stock
$5.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Expansion Tank Cap - Black

ES#3690266 - 5Q0121321 - Expansion Tank Cap - Black - Keep proper pressure in your coolant system - Vaico - Audi Volkswagen Porsche

Keep proper pressure in your coolant system affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
We Price Match - Give Us A Call or Chat!

Brand:
Vaico - Corporate Logo
ES#:
3690266
Mfg#:
5Q0121321
Ships on Sep 29, 2026
$18.99

This product was last offered at the strikethrough price on
04-02-2026

$12.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Expansion Tank Cap - Black

ES#4004591 - 5Q0121321 - Expansion Tank Cap - Black - Keep proper pressure in your coolant system - Rein - Audi Volkswagen Porsche

Keep proper pressure in your coolant system affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
We Price Match - Give Us A Call or Chat!

Brand:
Rein - Corporate Logo
ES#:
4004591
Mfg#:
5Q0121321
In Stock
$16.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Expansion Tank Cap - Black

ES#4818658 - 5Q0121321 - Expansion Tank Cap - Black - Keep proper pressure in your coolant system - Bremmen Parts - Audi Volkswagen Porsche

Keep proper pressure in your coolant system affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms 10X Entries For Our 25th Anniversary Sweepstakes!

Brand:
Bremmen Parts - Corporate Logo
ES#:
4818658
Mfg#:
5Q0121321
Ships in 1 Business Day
ON SALE! SAVE 24%
$15.99

This product was last offered at the strikethrough price on
05-02-2026

$12.23 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Expansion Tank Cap

ES#4220586 - 8E0121321 - Expansion Tank Cap - Plastic pressure cap for expansion tank - Rein - Audi

Plastic pressure cap for expansion tank affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
We Price Match - Give Us A Call or Chat!

Brand:
Rein - Corporate Logo
ES#:
4220586
Mfg#:
8E0121321
In Stock at Vendor
$18.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Expansion Tank Cap

ES#2091199 - 8E0121321 - Expansion Tank Cap - Plastic pressure cap for expansion tank - Genuine Volkswagen Audi - Audi

Plastic pressure cap for expansion tank affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
2091199
Mfg#:
8E0121321
In Stock
11% off MSRP

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$55.99

This product was last offered at the strikethrough price on
02-26-2026

$49.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Expansion Tank Cap

ES#2709072 - 8E0121321 - Expansion Tank Cap - Plastic pressure cap for expansion tank - URO - Audi

Plastic pressure cap for expansion tank affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
We Price Match - Give Us A Call or Chat!

Brand:
URO - Corporate Logo
ES#:
2709072
Mfg#:
8E0121321
Ships in 2 Business Days
$6.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Expansion Tank Cap

ES#2802007 - 1J0121321B - Expansion Tank Cap - Keep proper pressure on your coolant - Rein - Audi Volkswagen Porsche

Keep proper pressure on your coolant affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
We Price Match - Give Us A Call or Chat!

Brand:
Rein - Corporate Logo
ES#:
2802007
Mfg#:
1J0121321B
Ships on Jun 22, 2026
$10.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Let us help you find the parts that fit your Audi

ECS Tuning is not affiliated with any automobile manufacturers.
Manufacturer names and/or part numbers are used only for identification purposes.

Terms of Use Privacy Policy ECS Tuning is part of Enthusiast Auto Holdings