Fiat 149B / 280A (Sofim)

The diesels of the early Fiat Ducato and its Peugeot and Citroën twins — the 1.9 149B, its turbocharged 280A and the Sofim 8140 family beside them.

⚑ Sofim was a joint venture between Fiat, Alfa Romeo and Saviem, which is why the same engine turns up under four badges and why the parts trail is confusing: searching 8140 finds material that searching Ducato does not.

They are indirect-injection engines with mechanical pumps — no rail, no filter, nothing to regenerate — and nothing to read with a scan tool. Diagnosis is physical: compression, glow plugs, injection pump timing and injector nozzles account for nearly the whole fault list.

These are working vans and most survivors have very high mileage, so wear rather than failure is the normal finding.

The DW8 and DW10 that followed in the PSA-badged vans are different engines with their own pages here.