An engine that cuts out while driving is a safety problem: with the engine off, the power steering and brake servo stop assisting. The most frequent causes are fuel supply, phase sensors or a faulty electrical earth.
What to do at that moment
- Hold your line: steering and brakes work but need much more effort
- Switch on the hazard lights and pull over safely
- Try to restart only when stationary
Most common causes
- Intermittent crank or camshaft sensor (often cuts out when hot)
- Fuel pump on its way out
- Clogged diesel filter or air drawn into the circuit
- Corroded engine earth or worn wiring
- Relay or inertia switch
- Dirty throttle body on petrol engines (stalling at idle)
- Immobiliser or aftermarket alarm problems
What to do right away
- Note when it happens: when hot, in corners, when braking, over bumps. It is the most useful clue
- Do not put it off: an intermittent fault tends to get worse
- Have the fault memory and the values recorded at the moment of the cut-out checked
How MasterTuning helps
We do not replace parts by trial and error: we read the real values from the ECU (pressures, flow rates, corrections, temperatures) and identify the component responsible. Then we repair and recalibrate the software where needed. Centres throughout Italy.
Does your car have this symptom? Book a diagnosis at your nearest MasterTuning centre.