Audi A5 Turbo

Turbo Audi A5: from the 2.0 TDI 170 hp to the V6 biturbo units – which turbo matches which engine code?

The answer comes down to two key points: the stated power output alone is not enough – it is the engine code stamped on the block that determines the exact reference. On the A5, several codes can share the same engine capacity and the same advertised power output whilst using different turbos – this is particularly true of the 2.0 TDI, which comes in 170 hp (codes CAHA, CDNB, CDNC), 177 hp (CAPA, CCWA, CCWB, CCLA), 190 hp (CPNB, CSWB) and 190 hp 40 TDI (CRTC, DTP, DTPA) variants.

Diesel: three families, three turbo architectures

The 2.7 TDI (CAMA, CAMB) and the 3.0 TDI – whether in 211/240 hp form (CGKA, CGKB, CGLC) or 218/272 hp form (CNHA, CZJA, DDAA) – each run 2 turbos in sequence; references 059145722_ and 059145721_ are not interchangeable between these 2 families. On these V6 blocks, the most common signs of wear are a whistling noise under load and a gradual loss of boost pressure, often caused by lubrication breakdown due to contaminated oil or EGR fouling acting upstream. The 2.0 TDI uses a single variable-geometry turbo; references 03L145701_, 03L145702_ and 04L253056_ cover the different generations, but they cannot be substituted without first checking the engine code.

Petrol: from the 2.0 TFSI to the V6 biturbo RS 5

The 2.0 TFSI (CAEA, CAEB, CFKA, CAED, CPMA, CPMB, CNCB) covers outputs from 180 to 220 hp; references 06H145702_ and 06H145703_ come in numerous variants depending on the exact generation of the block. The 3.0 TFSI 354 hp (CGKB, DCAB, MDCAB) and, above all, the 2.9 TFSI V6 biturbo RS 5 450 hp (DGPA, MDGPA, DGRC, MCSZA, DECA, CWGD) have a biturbo architecture with dedicated references (06M145702_, 06M145704_); confusing the 2 turbo positions on the V6 is a common identification error. On all petrol blocks, an air leak in the intake circuit or a faulty sump gasket frequently precedes CHRA failure – identifying and resolving this root cause is essential before any replacement.

Only the 2.0 TDI 170 hp is available with both a new turbo and a reconditioned turbo. All other engine variants are covered by a new turbo only, sold on a direct-sale basis with no old unit to return.