Used Alfa Romeo 155 Catalytic Converter

Yes, the Alfa Romeo 155 (produced 1992–1997) was fitted with a catalytic converter on petrol engine variants, as it fell within the era of early catalytic converter adoption in Europe and the UK. Diesel variants of the 155 did not use a catalytic converter in the modern sense, as diesel cat-and-DPF systems came later than this model's production run. If you have a petrol 155, a cat is a genuine part of your exhaust system; if you have a diesel, the part you may be looking for is simply a standard exhaust section rather than a catalytic converter.

The 155 received a facelift in 1995, and while the basic body and some mechanical components carried over, exhaust system components including catalytic converters can differ between pre-facelift and post-facelift cars depending on the specific engine code fitted. The engine code is the key thing to match here — two 155s with the same engine code are more likely to share a compatible cat than two cars of different years with different engine variants. Because catalytic converter interchange specifics are strong confirm-with-breaker territory, always check the engine code from your registration with the breaker before purchasing.

No, trim level does not affect catalytic converter fitment on the 155 — the cat follows the engine, not the trim or equipment level. What matters is your engine code and fuel type, so a 155 with the same engine as another regardless of trim specification should use the same cat. Focus on providing the breaker with your exact engine code rather than your trim name, and fitment should be straightforward to assess from there.

Almost certainly not — different engine displacements typically use different catalytic converters sized and tuned to that specific engine's exhaust flow and emissions calibration, so a 1.8 and a 2.0 cat are unlikely to be directly interchangeable even within the Twin Spark family. The engine code is the reliable matching point here, not just the fuel type or engine family name. Confirm the engine code from your V5 or registration with the breaker to make sure you're sourcing the right unit.

Potentially yes, since the 155 is a European model and the underlying engineering is the same, but the emissions specification the cat was built to meet can vary by market and production year, and fitting a cat that doesn't meet the correct standard could cause an MOT failure on UK emissions testing. The safe approach is to match the engine code and confirm with the breaker that the sourced cat was built to the appropriate emissions specification for your car's year. A reputable breaker will be able to cross-reference this against your registration rather than relying on appearance alone.

The used cat needs to match your engine code and have been manufactured to the correct emissions standard for your car's year of registration — fitting a visually similar cat from a different engine variant or a looser emissions specification can result in a test failure even if it bolts on physically. Catalytic converter interchange specifics are genuinely complex and are best confirmed directly with the breaker using your full registration or engine code rather than relying on year or model alone. A good breaker will be able to tell you the origin vehicle's engine code so you can compare it against your own before committing to the purchase.