Mazda Mazda3 IV (BP) (2019 – 2025)

Reliability score : 8.8/10

The fourth-generation Mazda3 (internal code BP) marks a decisive turning point for the Hiroshima-based manufacturer, with a clearly assumed positioning towards the premium segment. Featuring the refined 'Kodo' design, it offers interior finish quality that rivals German benchmarks. Technically, it is based on the Skyactiv-Vehicle Architecture platform. Although global demand has massively shifted towards gasoline (with the innovative e-Skyactiv G and X engines), Mazda initially offered a 1.8 Skyactiv-D diesel engine. The latter had a very short career in Europe (withdrawn in late 2020/early 2021 depending on the country) due to taxation and the decline in popularity of diesel, but it remains relevant in the used car market for high-mileage drivers. Overall, the Mazda3 BP is an extremely re

⚠️ Weaknesses

🎯 Verdict

The Mazda3 (BP) is one of the most reliable compact cars on the market. If you are specifically targeting the 1.8 Skyactiv-D diesel engine, it is a wise choice only if you are a high-mileage driver. Its immense advantage lies in the absence of an AdBlue system, saving you from the ruinous failures that plague contemporary French or German diesels. However, it does not tolerate exclusive urban use (risk of clogging and oil dilution). If your annual mileage is less than 20,000 km, confidently opt for the gasoline engines (e-Skyactiv G or X), which are models of reliability and fuel efficiency.

Common issues

Encrassement du filtre à particules (FAP/DPF) Medium
🔧 80 000 – 150 000 km (variable selon usage)
💶 300 – 800 € (régénération forcée/nettoyage) ; 1 500 – 3 000 € (remplacement)
Privilégier les longs trajets réguliers pour permettre la régénération automatique.
Encrassement de la vanne EGR Medium
🔧 100 000 – 180 000 km
💶 350 – 700 € (nettoyage/remplacement)
Une conduite souple et des nettoyages préventifs peuvent prolonger sa durée de vie.
Dysfonctionnement du système AdBlue (SCR) moyenne à haute
🔧 100 000 – 200 000 km
💶 500 – 1 500 € (selon le composant défectueux : capteur, pompe, injecteur)
Utiliser un AdBlue de qualité, éviter de rouler avec un réservoir vide.

Estimated maintenance costs

Oil change £90 – 160
Timing chain £700 – 1 300 (si remplacement nécessaire, rare)
Clutch £900 – 1 600
Complete brakes £300 – 550
Estimated annual budget £700 – 1 300

Indicative estimates (independent garage, UK market). Prices vary by region and year.