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Details
| Specification | Value |
|---|---|
| Brand | AIC |
| Pressure [bar] | 1.2 bar |
OE numbers (9)
Search by this OE number to find compatible parts
- AUDI / VAG / VW—171 121 321B
- AUDI / VAG / VW—171 121 321C
- AUDI / VAG / VW—171 121 321D
- AUDI / VAG / VW—171 121 321F
- AUDI / VAG / VW—443 121 321
- PORSCHE—996 106 447 00
- PORSCHE—996 106 447 01
- PORSCHE—996 106 447 03
- PORSCHE—996 106 447 04
Where this part fits
Original-fit position for OE 443121321. The red ring marks where this part installs on the vehicle.
About this product
The AIC Cap Coolant Tank (51171) is a professional-grade replacement component engineered for long service life and reliable operation across all conditions your vehicle encounters. The part is built to the following specification: Pressure [bar]: Steel, Aluminium bar, Colour: Rubber, Material: Plastic. Each dimension is checked against the OEM reference to ensure the component seats and functions correctly first time. Verified to fit AUDI, PORSCHE, SEAT, VW models. All compatibility data is cross-checked against the TecDoc database — select your vehicle to confirm the part matches your specific engine and year. This part supersedes original equipment references: --, 00253, 002-60-02032, 02269 and 41 more. Matching these numbers confirms a like-for-like replacement with no loss of function. AIC is a recognised supplier of automotive replacement components to independent workshops and dealer networks across Europe. All parts are sourced from authorised distribution channels and carry full manufacturer traceability — you receive exactly the same component supplied to professional garages and dealer workshops. If fitment or specifications do not match your vehicle, our technical team can help identify the correct alternative — use the vehicle selector or contact us with your VIN for a guaranteed-fit recommendation. Replacing worn components on schedule preserves your vehicle's safety, reliability, and resale value — and aftermarket parts from established brands deliver OEM-equivalent performance at a fraction of the dealer price. Every part is dispatched with tracked delivery and a 14-day money-back guarantee with hassle-free returns.
Suitable cars
Equivalent products (36)
Show all 36 OE numbers
Cap Coolant Tank AIC 51171 — compatible car models
| Car models | AUDI: 100 C1 Coupe (817), 100 C1 Saloon (801, 803, 805, 807, 811, 813, F104), 100 C2 Avant (435, 436), 100 C2 Saloon (431, 433, 434), 100 C3 Avant (445, 446), 100 C3 Saloon (443, 444), 100 C4 Avant (4A5), 100 C4 Saloon (4A2), 200 C2 Saloon (437, 438), 200 C3 Avant (447, 448) (+20 more) |
|---|---|
| Engines | 1.9; 1.6; 1.8; 2.0 E; 2.0; 2.1 5E; 2.1 Turbo quattro; 1.1; 1.5; 1.3; 1.4; 1.6 E; 1.6 TD; 2.4; 2.5 TDI (+1 more) |
| Year of manufacture | 1968-2010 |
| Manufacturer article number (MPN) | 51171 |
| OE part numbers | 171 121 321B, 171 121 321C, 171 121 321D, 171 121 321F, 443 121 321, 996 106 447 00, 996 106 447 01, 996 106 447 03, 996 106 447 04 |
Compatibility check
Loading vehicle data…
Please wait while we load vehicle compatibility information.Description and what's included
AIC 51171 Original AIC Quality. Colour: 5. Material: 6. Pressure [bar]: 1,2 bar
- 1x Cap Coolant Tank
Shipping, returns, warranty
Free UK delivery on orders over £99.00. Tracked standard shipping.
- Standard delivery: 5–9 business days
- Order before 5pm — ships the next working day
- Free returns within 14 days
- All parts backed by manufacturer warranty
Warranty: 12-month manufacturer warranty on all parts. 14-day money-back guarantee if the part doesn't fit your vehicle.
Frequently Asked Questions
Is this Cap Coolant Tank compatible with my car?
This Cap Coolant Tank fits AUDI, PORSCHE, SEAT, VW vehicles. Use the vehicle selector at the top of the page to check exact compatibility — enter your car's make, model, and engine for a confirmed fitment match. All fitment data is verified through TecDoc.
What specifications does this AIC Cap Coolant Tank have?
This AIC Cap Coolant Tank has the following specifications: Pressure [bar]: 1,2 bar; Colour: 5; Material: 6. Check the full specifications table above for complete details.
What OE part numbers does this Cap Coolant Tank replace?
This Cap Coolant Tank replaces OE part numbers: 171 121 321B, 171 121 321C, 171 121 321D, 171 121 321F, 443 121 321, 996 106 447 00, 996 106 447 01, 996 106 447 03 and 1 more. Cross-reference these numbers with your vehicle's original part number to confirm compatibility.
How much does a Cap Coolant Tank cost?
Cap Coolant Tank prices vary depending on brand, specifications, and vehicle compatibility. Check the current price above for this AIC Cap Coolant Tank. All parts come with our 14-day money-back guarantee.
How do I know when to replace my Cap Coolant Tank?
Regular inspection of your Cap Coolant Tank is recommended as part of routine vehicle maintenance. Watch for changes in performance, unusual noises, or visual signs of wear. Consult your vehicle's owner manual for manufacturer-recommended replacement intervals specific to your make and model.
What tools do I need to replace a Cap Coolant Tank?
Tools required vary by vehicle make and model. Generally, a basic socket set, screwdrivers, and vehicle-specific tools may be needed. We recommend consulting a workshop manual for your specific vehicle, or having the Cap Coolant Tank fitted by a professional mechanic.
Can I use this part as a replacement for OE 171 121 321B?
Yes, this AIC Cap Coolant Tank is a direct replacement for OE part number 171 121 321B. It is manufactured to meet or exceed original equipment specifications, ensuring proper fitment and performance. All cross-reference data is verified through TecDoc.
Related categories
Common OE numbers for this part
Common original equipment numbers linked to stocked alternatives.
