<P> A glowplug ( alternatively spelled as glow plug or glow - plug ) is a heating device used to aid starting diesel engines . In cold weather , high speed diesel engines can be difficult to start because the mass of the cylinder block and cylinder head absorb the heat of compression , preventing ignition ( which relies on that heat ) . Pre-chambered engines use small electric heaters ( glowplugs ) inside the pre-chambers . Direct - injected engines have these glowplugs in the combustion chamber . The glowplug is a pencil - shaped piece of metal with a heating element at the tip . This heating element , when electrified , heats due to its electrical resistance and begins to emit light in the visible spectrum , hence the term glowplug . The visual effect is similar to the heating element in a toaster . The fuel injector spray pattern then impinges directly upon the hot tip of the glow plug during the injection of fuel at top dead center . This ignites the fuel even when the engine is insufficiently hot for normal operation , which reduces the cranking time to start the engine . </P>
<P> A glowplug ( alternatively spelled as glow plug or glow - plug ) is a heating device used to aid starting diesel engines . In cold weather , high speed diesel engines can be difficult to start because the mass of the cylinder block and cylinder head absorb the heat of compression , preventing ignition ( which relies on that heat ) . Pre-chambered engines use small electric heaters ( glowplugs ) inside the pre-chambers . Direct - injected engines have these glowplugs in the combustion chamber . The glowplug is a pencil - shaped piece of metal with a heating element at the tip . This heating element , when electrified , heats due to its electrical resistance and begins to emit light in the visible spectrum , hence the term glowplug . The visual effect is similar to the heating element in a toaster . The fuel injector spray pattern then impinges directly upon the hot tip of the glow plug during the injection of fuel at top dead center . This ignites the fuel even when the engine is insufficiently hot for normal operation , which reduces the cranking time to start the engine . </P>
what do glow plugs do in a diesel engine
what do glow plugs do in a diesel engine
start the engine
start the engine