The Audi A4 B7 (internal designation Typ 8E) is technically a heavy facelift of the outgoing B6 generation rather than an entirely new platform. However, it introduced significant changes: revised steering, suspension geometry borrowed from the S4/A6, and the introduction of Audi's signature 'Singleframe' grille. Crucially, the B7 marked the widespread introduction of direct-injection petrol engines (FSI and TFSI) and piezo-injector diesels. While build quality and interior finish remain benchmark-setting for the era, the B7's reliability heavily depends on the chosen powertrain. The petrol lineup ranges from bulletproof older MPI designs to early, sometimes problematic, direct-injection units.
The Audi A4 B7 is a beautifully built car that bridges the gap between older, simpler Audis and modern, highly complex ones. If you are looking for a petrol model, the 1.8T is the safest bet for reliability and tuning, while the 2.0 TFSI is excellent provided you are willing to proactively maintain the cam follower and PCV system. Avoid the 3.2 FSI and S4 4.2 V8 unless you have a massive budget for timing chain repairs. Absolutely avoid the Multitronic CVT transmission on front-wheel-drive models; seek out a manual or a Quattro model (which uses the robust ZF Tiptronic). Buy strictly on maintenance history, not mileage.