Diesel engines do not have spark plugs; they have glow plugs. United Diesel Repair knows all about these crucial automotive parts, and we are going to share our knowledge with you. If you drive a diesel automobile, it’s a good idea to know a thing or two about glow plugs, so here we go!
Glow Plug 101
Perhaps we should have said diesel engine 101, because in order to understand the need for glow plugs, you need to understand a little bit about diesel engines. One of the reasons why diesel engines produce more power than gasoline engines do is that they run much hotter and they produce much higher compression. A diesel engine needs heat to start and to continue to run. Without heat, the engine is unable to fire up. A diesel engine’s cylinder block and head are heat hogs, leaving the combustion chamber cold when the engine isn’t running.
Diesel engines rely on glow plugs to produce the heat in the combustion chamber that they need to fire up. A glow plug is not a spark plug, although their end-game is the same. A spark plug produces a spark to set the air and fuel in the combustion chamber on fire. This is what starts a gasoline engine. A glow plug produces the heat that is necessary for the diesel engine to fire up and run. It does not produce a spark, but it does produce much-needed heat.
Why Aren’t Spark Plugs Used in Diesel Engines?
It can be true that where there is heat there is fire, but spark plugs do not produce enough heat to start the combustion in a diesel engine. Yes, the spark plugs generate a spark, but this does not produce the heat that the diesel engine needs. It takes a lot more heat than a spark plug it can produce to fire up the air and diesel fuel in the engine’s combustion chamber. This is because cylinder compression is stronger.
Signs the Glow Plugs Are Going Bad
Another significant difference between spark plugs and glow plugs is their lifespan. Spark plugs continue to generate sparks until a gasoline engine is shut down. Glow plugs are only needed at the time of ignition in a diesel engine. As such, glow plugs last much longer than spark plugs do because they are only used when you turn on your diesel automobile. This does not mean that these parts don’t go bad. They do, eventually, and signs your diesel engines glow plugs are failing include
- A dead engine in cold weather
- Black exhaust when you try to start the car or truck
- Acceleration and power loss
- Bad diesel fuel mileage and efficiency
These are all signs of bad plugs, and we can help. United Diesel Repair is the best diesel repair shop in Flowery Branch, GA. We’d be happy to inspect your diesel engine glow plugs and, if they need replacing, change them out right away.
