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E90 Common Problems by Engine
How reliable each E90 sedan really is — N52, N54, N55, N20, the diesels and the S65 M3, the issues they share, and which engine to buy.
Read the guide →Buying the Sedan
328i vs 335i — Which to Buy
The smooth, reliable N52 328i versus the fast, tunable N54/N55 335i — the core decision on the sedan, with a full staged inspection.
Read guide →E90 Sedan Buyer's Guide
A sedan-specific walkthrough — 325i/328i/330i/335i trims, xDrive, options and the staged inspection that matters on a four-door.
Read guide →Sedan vs Coupe — Which E9x?
E90 four-door practicality versus the E92 coupe's style — doors, the M3, values and what it means to live with each.
Read guide →E90 M3 Sedan
The four-door S65 V8 M3 — the practical M car. What's unique to the sedan and what it shares with the coupe.
Read guide →The Engines
DIY & Service
Coupe, Touring or Convertible?
The E92 coupe, E91 Touring and E93 convertible share the E90's engines and mechanicals. Head to the E9x hub for those bodies and the coupe-specific buyer's guide and tuning.
Go to the E92 / E9x hub →