Audi A4 2.0 TFSI Turbo

The A4's 2.0 TFSI is petrol-only — what does that actually mean for the turbo?

Unlike the 2.0 TDI section, this catalogue is entirely petrol — no diesel units, no variable-vane geometry. The 2.0 TFSI turbos all operate on the principle of fixed geometry with a wastegate, which fundamentally changes the failure patterns: with no variable vanes to maintain, faults concentrate instead on the CHRA (bearings, axial play), oil-seal integrity, and the thermal resistance of materials exposed to petrol exhaust gases, which run hotter than diesel exhaust.

Two families of manufacturer references depending on engine generation

This section distinguishes two groups of engine codes. The first — BGB, BPG, BPJ, BUL, BWE, BWT, BYK, CAEA, CAEB, CDNB, CDNC, CFKA, CNCB, CNCD, CYMC, CYND, CYPA, CYRB, DBPA, DDWA — covers the 2.0 TFSI engine in its broadest range and corresponds to manufacturer references including 06D145701xx and 06H145702xx. The second group — CAEA, CAEB, CAED, CDNB, CDNC, CDND, CFKA, CNCB, CPMA, CPMB — applies specifically to the 180 hp, 211 hp and 220 hp variants and uses references in the 06L145702xx and 06L145722xx range. Several codes (CAEA, CAEB, CDNB, CDNC, CFKA, CNCB) appear in both groups, but the turbo selected is not necessarily identical: the stated output and year of production remain the deciding factors when choosing the correct manufacturer reference.

Failure causes specific to petrol turbos with a wastegate

On a direct-injection petrol engine such as the 2.0 TFSI, turbos suffer primarily from carbon deposits on the turbine side (degraded oil that cokes on contact with high temperatures), excessive axial play in the bearings after a hot engine shutdown without a cool-down period, and wear of the wastegate actuator leading to a boost fault. Before any replacement, it is essential to address the identified root cause — oil quality and circuit, intake sealing, condition of the vacuum system — otherwise the new turbo will present the same symptoms (whistling, blue smoke, power loss, limp-home mode). All turbos listed on this page are brand-new turbos, sold as a straightforward purchase.