The Glow Plug
#1
Senior Member
Thread Starter
The Glow Plug
Hello, everyone:
I was stopped at a light last night next to an old 300 D, and listening to its clackity-clack, it made me recall when one of my cousins drove an Oldsmobile Cutlass diesel about 20 years ago. We fondly called it "el camión," which in Spanish means "the truck," because of the sound of the old diesel engine. I distinctly remember the yellow "Glow Plug" light on the dashboard, which had to be allowed to go out before the engine could be safely started, and that got me thinking. What is it about today's diesels that lets the driver just start it up and go? I know it still must be allowed to properly warm up, but that's much different to sitting there waiting for a light to go out. Any thoughts?
I was stopped at a light last night next to an old 300 D, and listening to its clackity-clack, it made me recall when one of my cousins drove an Oldsmobile Cutlass diesel about 20 years ago. We fondly called it "el camión," which in Spanish means "the truck," because of the sound of the old diesel engine. I distinctly remember the yellow "Glow Plug" light on the dashboard, which had to be allowed to go out before the engine could be safely started, and that got me thinking. What is it about today's diesels that lets the driver just start it up and go? I know it still must be allowed to properly warm up, but that's much different to sitting there waiting for a light to go out. Any thoughts?
#2
MBWorld Fanatic!
Join Date: Feb 2004
Location: South Orange County, CA
Posts: 5,143
Likes: 0
Received 1 Like
on
1 Post
4 wheels
Common Rail Direct Injection. Diesel is injected into the cylinder at 25,000 PSI so it literally combusts on its own at that pressure. That is why you don't have glow plugs. I think MBZ invented this technology.
#4
Member
Join Date: Feb 2007
Location: Bucks County PA
Posts: 196
Likes: 0
Received 0 Likes
on
0 Posts
MB
I kinda miss that distinct MB diesel sound just like the chain belt of the earlier VW beetle and air-cooled Porsches. You always knew what was coming without even looking!
#6
Senior Member
Join Date: Dec 2006
Location: Scottsdale, AZ
Posts: 405
Likes: 0
Received 1 Like
on
1 Post
2007 GL320 CDI, 2001 TJ Rockcrawler, 2005 Scoobie STI
The new generation glow plugs just reach starting temperature much faster than the old ones. If you leave it parked outside overnight in a cold snowy environment, you will notice that it takes a bit longer for the glow light to turn off. (3 seconds instead of 1 second)
My GL has the Keyless Go system, so when I press the start button, it waits for the glowplugs to warm up before the engine actually turns over.