Engine Cutting Out While Driving

The first few seconds

1. Switch on hazard lights, press the clutch or move the selector to N, and let the vehicle coast.
2. Steer and brake firmly. Without the engine, power steering and brake assist stop working, but you can still steer and brake. It just needs noticeably more force.
3. Coast to a safe spot: to the right, into a lay-by, a car park, or the next exit, otherwise onto the hard shoulder.
4. Put on the hi-vis vest, get out, go behind the crash barrier. On the motorway, see Breaking down on the motorway.

What you can check afterwards

• Fuel: is the tank empty, or was the wrong fuel used? If it's the wrong fuel: don't restart, see Wrong fuel.
• Warning lights: is the battery or oil-pressure light on? See Warning lights in your car.
• Fuel pump: on some vehicles you hear a brief hum when switching on the ignition. If it's missing, the pump may have failed.
• Noises beforehand: jerking, a loss of power, or rattling give clues for the garage.

Common causes

• Fuel supply: a failed fuel pump or a blocked filter. The engine doesn't get enough fuel.
• Alternator: if it fails, it stops supplying the car with power. If the battery goes flat, the car stalls. Usually the red battery light comes on beforehand.
• Timing belt or chain: damage, for example to a tensioner pulley, can stall the engine. It must not be restarted afterwards, as that can cause major damage.
• Diesel particulate filter: a blocked filter can stall a diesel engine, often on high-mileage vehicles.

Don't just keep restarting

A second start attempt is fine if you're standing safely and no red light is on. But repeated cranking drains the battery further and can destroy the engine if there's timing-belt damage. If the engine stalls again after starting, or sounds unusual, leave it. The garage reads the fault memory, which is the first step to a diagnosis.

When you should call us

• The engine won't start again, or stalls immediately
• A red warning light or unusual noises before it stalled
• You're somewhere dangerous, such as a motorway, tunnel, or bridge

The vehicle is then taken to a garage on a flatbed. For hybrids and electric cars, that's the safe route anyway, see Towing an electric car.