I have the original Fiat CD for the Idea and have just had a look. Of the 1.3diesel it says...
CURRENT DEVELOPMENTS
These engines are fitted with ''Magneti Marelli Common Rail' high pressure electronic injection systems for fast diesel engines totally managed by a Multijet MJD 6JF electronic control unit.
PERFORMANCE
This engine is able to provide the following performance:
- maximum power 51 kW - 69 BHP EC at 4000 rpm;
- maximum torque 180 Nm EC at 1750 rpm.
DEVICES ADOPTED
These engines are fitted with the following emissions control devices:
- exhaust system with oxidising catalytic converter;
- E.G.R. exhaust gas recirculation system with heat exchanger;
- crankcase vapour/gas recirculation system.
STRUCTURE
The unit comprises the engine and all the systems required for its operation:
- fuel system;
- air turbocharging system;
- engine cooling system;
- exhaust system with catalytic converter;
- oil vapour recirculation system;
- E.G.R. exhaust gas recirculation system with heat exchanger;
The operation of these systems is optimized by an electronic control system governed by a control unit.
An understanding of the operating logic of the control unit gives an overall picture of the entire GROUP 10 system Characteristic of working principle
1060 DIESEL FUEL INJECTION.
CONSTRUCTION
Direct injection turbodiesel engine without precombustion chamber, 4 cylinders in line, 1248 c.c., four valves per cylinder with hydraulic tappets, two overhead camshafts with geared power transmission, supercharged with variable geometry turbocharger and intercooler, Magneti Marelli MJD 6JF Common Rail electronic fuel injection system.
So you don't have a lambda sensor as far as I can see