Glow plugBosnia and Herzegovina

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151. Glow plug

A glow plug is an electrical heating element used in diesel engines to help ignite the fuel during cold starting. It heats the combustion chamber so that the compressed air reaches conditions suitable for reliable combustion.

Modern glow plugs can continue operating briefly after the engine starts to improve combustion, reduce cold-start emissions and help the engine run smoothly while warming up.

Glow plug
Diesel preheating and glow-plug dashboard indicator symbol.
Wikimedia.org • Chris828 • CC0
What does a glow plug do?

A glow plug heats the combustion chamber of a diesel engine before and during cold starting so that the injected diesel fuel can ignite more reliably.

Do diesel engines use glow plugs instead of spark plugs?

Diesel engines normally ignite fuel through compression rather than an electrical spark. Glow plugs therefore assist cold combustion but do not continuously ignite the fuel in the same way that spark plugs do in a petrol engine.

What are signs of faulty glow plugs?

Possible signs include difficult cold starting, rough running shortly after startup, increased cold-start smoke or a glow plug or engine warning light. Similar symptoms can have other causes, so proper diagnosis may be necessary.

1 Bosnia and Herzegovina 2 Motorway 3 Quay 4 Give way 5 Roundabout 6 Railway crossing 7 Traffic lights 8 International border 9 Reversing 10 City limit 11 Tourist attraction 12 Bus 13 Police 14 Ambulance 15 Taxi 16 European emission standard 17 Pothole 18 Path 19 Particulates 20 Air pollution 21 Rush hour 22 Road code 23 Street gutter 24 Cargo bike 25 Forestry vehicle 26 Construction vehicle 27 Semi-trailer truck 28 Trolleybus 29 Speed pedelec 30 Delivery vehicle 31 Idling 32 Tow truck 33 Four-wheel drive 34 Bicycle 35 Motorcycle equipment 36 Rail track 37 Caravan 38 Trailer 39 Tow hitch 40 Fire truck 41 Siren 42 Convoy 43 Emergency vehicle lighting 44 Agricultural machinery 45 Electric bicycle 46 Electric vehicle 47 Pedelec 48 Quadricycle 49 Microcar 50 All-terrain vehicle 51 Van 52 Recreational vehicle 53 Scooter 54 Trikke 55 Personal mobility device 56 Skateboard 57 Segway 58 Kick scooter 59 Roller skates 60 Mailman 61 Hitchhiker 62 Toddler 63 Child 64 Disability 65 Motorail 66 km/h 67 mph 68 Speedometer 69 Ride height 70 Dirt road 71 Driving 72 Start-stop system 73 Manual transmission 74 Automatic transmission 75 Throttle 76 Tachometer 77 Steering wheel 78 Power steering 79 Visual scanning 80 Mirror 81 Fuel 82 Fuel gauge 83 Petrol 84 Diesel 85 Diesel exhaust fluid 86 Car insurance 87 First aid kit 88 Fire extinguisher 89 High-visibility clothing 90 First aid 91 Concrete step barrier 92 Barriers 93 Vehicle lights 94 Street lights 95 Dipped beam 96 High beam 97 Fog lights 98 Front fog lights 99 Rear fog lights 100 Side lights ... 101 Turn signals 102 Hazard lights 103 Dashboard lights 104 Bicycle lighting 105 Bicycle bell 106 Headlight flashing 107 Seat belt 108 Child restraints 109 Head restraints 110 Airbag 111 ABS 112 Esp 113 Traction control system 114 Helmet 115 Bicycle helmet 116 Hands-free 117 Smartphone 118 GPS 119 Brake 120 Handbrake 121 Brake fluid 122 Tyres 123 Tyre code 124 Winter tyres 125 Tyre pressure 126 Snow chains 127 Bicycle tyre 128 Continuous track 129 Gross Vehicle Weight 130 Gross Vehicle Weight Rating 131 Cargo 132 Car body 133 Trunk 134 Roof rack 135 Windscreen 136 Emergency hammer 137 Car battery 138 Traction battery 139 Suspension 140 Shock absorber 141 Spring 142 Exhaust 143 Exhaust gas 144 Soot 145 Catalytic converter 146 Engine 147 Petrol engine 148 Diesel engine 149 Electric motor 150 Timing belt 151 Glow plug 152 Cylinder 153 Engine oil 154 Coolant 155 Maintenance 156 Spare tyre 157 Flat tyre 158 Jack 159 Vehicle inspection 160 Key 161 Dashboard 162 Windscreen wiper 163 Doors 164 Glovebox 165 Visibility 166 Rain 167 Fog 168 Hail 169 Sunlight 170 Sunglasses 171 Salt 172 Air conditioning 173 Hydroplaning 174 Distraction 175 Emotions 176 Road rage 177 Health 178 Epilepsy 179 Night blindness 180 Visual impairment 181 Fatigue 182 Defects 183 Traffic violation 184 Alcohol 185 Alcohol control 186 Ignition interlock device 187 Breath test 188 Breath analysis 189 Blood alcohol content 190 Blood test 191 Saliva test 192 Drugs 193 Medication 194 Penalties 195 Speeding 196 Smoking 197 Traffic enforcement camera 198 Accident 199 Injuries 200 Nosebleed 201 Damage 202 Breakdown 203 Warning triangle 204 Traffic rules 205 Driving school 206 Traffic signs