Alfa Romeo Turbo

Alfa Romeo turbos from the JTD to the JTDM and MultiAir era: how to choose the right one

Every turbo in this collection is sold new — no reconditioned parts, no exchange basis. This immediately shapes your decision: for a common engine whose turbo is still readily available, a new OEM-reference turbo is the straightforward route. For a rare block or an older engine — such as certain 1.9 JTD units from the early 147, or the 2.2 JTD Q4 from the 159 — limited supply may make rebuilding your own unit the more sensible option, depending on the condition of the housing and bearings. If your engine is not listed in the catalogue, it is worth asking before you order.

Diesel: the JTD and JTDM families — turbos are not interchangeable

The Alfa Romeo diesel range spans two clearly distinct generations. The first covers the 1.9 JTD in several power variants — 101, 105 and 120 hp — fitted to the 147, 156 and Giulietta, with different engine codes depending on the variant: 182B9000, 223A7000 and 223B1000 for the 101/105 hp versions; 186A9.000, 192A8.000 and 937A3000 for the 120 hp version. These codes are not mutually compatible, and engine capacity alone is not enough to identify the correct turbo. The second generation introduces the 2.0 JTDM and 1.6 JTDM, found predominantly in the Giulietta and Giulia. Here again, several engine codes exist for the same quoted power output: the 2.0 JTDM covers codes 844 A2.000, 939 B3.000 and 939 B4.000 for the 136, 163 and 170 hp versions, and 940A4000 for a further 170 hp variant. Only the engine code stamped on the block removes any ambiguity.

The 1.3 MultiJet fitted to the MiTo comes in two power outputs (80/84 hp and 95 hp) with distinct codes — 199 B4.000, 199 B8.000 and 223 A9.000 on one side; 199 B1.000 and 330 A1.000 on the other. Confusing these two families when ordering is the most common mistake made with this small-capacity engine.

Petrol: 1.4 TB and 1.4 MultiAir — two different architectures

On the petrol side, the 1.4 Turbo MultiAir (codes 955 A2.000 and 955 A7.000, 135 hp in the Giulietta) is distinct from the 1.4 TB in standard form, fitted to the MiTo in 105, 116 and 120 hp outputs. Both families share the same engine capacity but use different intake management systems; the turbo is not the same. On fixed-geometry, wastegate petrol engines, the most common causes of failure remain lubrication breakdown at start-up and oil residue fouling the CHRA. Addressing the root cause — oil quality, condition of the lubrication circuit, bearing play — before refitting is essential, regardless of which turbo you choose.