Seat Alhambra diesel injection fault

High fuel consumption, reduced power, stalling, and smoke all point to fuel delivery issues. Have you checked the air filter and fuel filter? When was the last maintenance performed on the fuel system?

Air filter was replaced 5000km ago, fuel filter at 130000km. What readings should I expect when testing the component's cable and plug connection?

Given those symptoms and mileage, alongside your component suspicion, a defective connection is plausible. Without diagnostic equipment, precise readings are difficult to determine. I suggest visiting a workshop equipped to diagnose diesel injection systems.

Acknowledged. The defective plug connection on the injection system was indeed the source of the issue. Repair cost was 95€. Thank you for your assistance.