IdlingIreland

Learn traffic rules with clear explanations and visual examples in our illustrated book, designed to make studying simple and engaging.


65. Idling

Idling means allowing a vehicle's engine to continue running while the vehicle is stationary and the engine is not being used to move the vehicle. This may occur while waiting, parking, loading or unloading or before beginning a journey.

Unnecessary idling consumes fuel and produces exhaust emissions, air pollution and noise. Many countries or local authorities restrict prolonged or unnecessary idling, although exceptions may apply when the engine is required for safety, technical equipment or another necessary purpose.

A stationary vehicle with its engine running is idling. (Volkswagen Golf)
Wikimedia.org • Spacekid • CC0
What is idling?

Idling means keeping a vehicle's engine running while the vehicle remains stationary and the engine is not being used to propel it.

Why should unnecessary idling be avoided?

Unnecessary idling uses fuel, produces exhaust emissions and creates noise without moving the vehicle.

Is idling illegal everywhere?

No. Rules differ between countries and local authorities. Some prohibit unnecessary idling generally, while others restrict it only in particular locations or circumstances.

Does an idling engine still produce exhaust emissions?

Yes. A combustion engine continues to produce exhaust gases while running even though the vehicle is not moving.

Does idling use fuel?

Yes. A combustion engine consumes fuel while it remains running, even when the vehicle is stationary.

Should you leave the engine running while waiting for someone?

Where it is safe and legal to switch the engine off, unnecessary prolonged idling should generally be avoided. Local rules may specifically require the engine to be switched off.

Is waiting at a red traffic light the same as parking with the engine idling?

No. A vehicle temporarily prevented from moving by traffic conditions is different from a vehicle voluntarily parked or waiting. The rules concerning engine shutdown may therefore differ.

Can an engine remain running when vehicle equipment needs power?

Some laws provide exceptions when the engine is genuinely required to operate refrigeration, hydraulic equipment, emergency equipment or another essential system. The precise exceptions depend on local law.

Should you rev the engine while stationary?

Unnecessary engine revving should be avoided because it increases noise, fuel consumption and emissions. It may also be specifically prohibited by local traffic or noise regulations.

Do electric vehicles idle?

Not in the conventional combustion-engine sense. An electric vehicle can remain stationary while switched on without an internal-combustion engine running, although electrical systems such as heating or air conditioning may still consume energy.

1 Ireland 2 Motorway 3 Residential area 4 Zone 5 Speed limit 6 Bike path 7 Pedestrian warning 8 Bridge 9 Speed bump 10 Toll road 11 Quay 12 Slope 13 Bus lane 14 Stop sign 15 Give way 16 Roundabout 17 Road narrowing 18 Pedestrian crossing 19 Railway crossing 20 Turn prohibition 21 School area 22 Crossing animals 23 Slippery road 24 Curve 25 Chevron 26 Wrong-way driving 27 Height limit 28 Weight limit 29 Radar speed sign 30 Priority at the next junction 31 Traffic lights warning 32 Pedestrian lights 33 Left-hand traffic 34 Driving licence 35 End of restriction 36 Parking 37 No parking 38 Reversing 39 U-turn 40 Hostel 41 Tourist attraction 42 Licence plate 43 Dangers 44 Cyclist 45 Bus 46 Police 47 Ambulance 48 Taxi 49 European emission standard 50 Pothole 51 Path 52 Particulates 53 Air pollution 54 Rush hour 55 Road code 56 2+2 Road 57 Street gutter 58 Cargo bike 59 Forestry vehicle 60 Construction vehicle 61 Semi-trailer truck 62 Trolleybus 63 Speed pedelec 64 Delivery vehicle 65 Idling 66 Tow truck 67 Four-wheel drive 68 Bicycle 69 Motorcycle equipment 70 Tram 71 Rail track 72 Caravan 73 Trailer 74 Tow hitch 75 Fire truck 76 Siren 77 Convoy 78 Emergency vehicle lighting 79 Agricultural machinery 80 Electric bicycle 81 Electric vehicle 82 Pedelec 83 Quadricycle 84 Microcar 85 All-terrain vehicle 86 Van 87 Recreational vehicle 88 Scooter 89 Trikke 90 Personal mobility device 91 Skateboard 92 Segway 93 Kick scooter 94 Roller skates 95 Mailman 96 Hitchhiker 97 Toddler 98 Child 99 Disability 100 Motorail ...