
What Breaks
Which engine to avoid? 28,000+ used car weaknesses say
1 follower
Which engine to avoid? 28,000+ used car weaknesses say
1 follower
No site tells you which engine to buy and which to avoid – until now. What Breaks is the largest used car weakness database: 28,000+ issues across 850+ models and 4,500+ engines, curated from real forums and service bulletins. Every engine gets a traffic light rating. Browse by make, model, engine – see what breaks, what it costs, and better alternatives. US coverage growing daily. Chrome Extension for Autotrader.com coming soon.







Hey Product Hunt! 👋
I built this because I was tired of buying used cars and discovering the engine was a known money pit. No website showed me at a glance: this engine good, that engine avoid.
What makes What Breaks different:
→ Engine-specific, not just model-level. A BMW 320d with the N47 engine (avoid, 8 issues) is a completely different car than one with the B48 (recommended, 2 issues). No other site shows this.
→ Real data, no AI hallucinations. Every weakness curated from owner forums, technical service bulletins and repair databases. Not generated by an LLM.
→ Traffic light system: recommended / neutral / avoid – instant clarity.
→ Fun rating, repair cost estimates, alternative models, vehicle-level weaknesses – all in one place.
→ Chrome Extension overlays all this directly in used car listings while you browse. Live for mobile.de (Germany), Autotrader.com support in development.
Demo of extension for mobile.de: https://youtu.be/n3B9JBilI0I
Demo of extension for autotrader.com - coming soon: https://youtu.be/LOCT6BqlnMM
→ No extension needed to explore the data – the full database is browsable on what-breaks.com right now. Search by make, model, engine and get all weaknesses, ratings and alternatives. The Chrome Extension just adds the convenience of seeing it directly inside the listing while you shop.
Full transparency: The database started in Germany (guteautoschlechteauto.de) where it covers 38,000+ weaknesses across 987 models. The US version is live and covers most major brands including US trucks like F-150 and Silverado. Coverage is growing daily – if your specific model or engine is missing, let me know and I'll prioritize it.
Would love your feedback – especially from anyone who's been burned by a bad engine choice before! 🚗