Question on Glow Plug timing

[Lefty5]

Someone told me that you can burn the glow plugs if you leave the
key on without starting the engine. I understood that there is a time
associated with the glow plugs and they would only stay on for a
controlled time depending on the ambient temp. Anyone know for
sure what the story is?

[thenubsterman]

i would say no you won't burn them up heck i leave my key on all the time, and when your vehicle runs your key is on. I'm pretty sure(95%) now a days on our trucks glow plugs are just for the intial fire, once it runs it doesn't use the glow plugs. hope this helps

[bismic]

Originally Posted by thenubsterman

i would say no you won't burn them up heck i leave my key on all the time, and when your vehicle runs your key is on. I'm pretty sure(95%) now a days on our trucks glow plugs are just for the intial fire, once it runs it doesn't use the glow plugs. hope this helps

Glow plug operation depends on a few parameters that the PCM monitors, but they can stay on for up to two minutes IIRC.

[thenubsterman]

alright, but they won't stay on forever like i think lefty was thinking