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Details
| Specification | Value |
|---|---|
| Brand | POLMO |
| MPN | 99.177 |
| Category | catalyst converter |
OE/OEM numbers (5)
Search by this OE number to find compatible parts
- AUDI / VW—4B0254200AX
- AUDI—4B0254200JX
- AUDI / VW—8D0131089BX
- AUDI / VW—8D0131090BX
- AUDI / VW—8D0131090X
Where this part fits
Original-fit position for OE 8D0131090BX. The red ring marks where this part installs on the vehicle.
About this product
The POLMO catalyst converter (99.177) 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: Catalytic Converter Type: 20. Each dimension is checked against the OEM reference to ensure the component seats and functions correctly first time. Verified to fit AUDI, 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: 04.0019, 12.195.65, 13.29.33, 20197 and 8 more. Matching these numbers confirms a like-for-like replacement with no loss of function. POLMO 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 from our UK warehouse with a 30-day money-back guarantee and free hassle-free returns.
Suitable cars
Equivalent products (7)
catalyst converter POLMO 99.177 — compatible car models
| Car models | AUDI: A4 B5 (8D2), A4 B5 Avant (8D5), A6 C5 (4B2, 4B4), A6 C5 Avant (4B5, 4B6); VW: PASSAT B5 (3B2), PASSAT B5 Variant (3B5) |
|---|---|
| Engines | 1.8 T |
| Year of manufacture | 1994-2006 |
| Manufacturer article number (MPN) | 99.177 |
| OE part numbers | 4B0254200AX, 4B0254200JX, 8D0131089BX, 8D0131090BX, 8D0131090X |
Compatibility check
Loading vehicle data…
Please wait while we load vehicle compatibility information.Description and what's included
POLMO 99.177 catalyst converter. Catalytic Converter Type: 20
- 1x catalyst converter
Shipping, returns, warranty
Free UK delivery on orders over £99.00. Express and standard shipping available.
- Standard delivery: 2-5 business days
- Express delivery: 1-2 business days
- 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 catalyst converter compatible with my car?
This catalyst converter fits AUDI, 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 POLMO catalyst converter have?
This POLMO catalyst converter has the following specifications: Catalytic Converter Type: 20. Check the full specifications table above for complete details.
What OE part numbers does this catalyst converter replace?
This catalyst converter replaces OE part numbers: 4B0254200AX, 4B0254200JX, 8D0131089BX, 8D0131090BX, 8D0131090X. Cross-reference these numbers with your vehicle's original part number to confirm compatibility.
How much does a catalyst converter cost?
This POLMO catalyst converter is available for £174.99. Catalyst converter prices vary depending on brand, specifications, and vehicle compatibility. POLMO parts offer a balance of quality and value, backed by our 14-day money-back guarantee.
How do I know when to replace my catalyst converter?
Regular inspection of your catalyst converter 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 catalyst converter?
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 catalyst converter fitted by a professional mechanic.
Can I use this part as a replacement for OE 4B0254200AX?
Yes, this POLMO catalyst converter is a direct replacement for OE part number 4B0254200AX. 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.
