glow plug question
Senior User
Joined: Jan 2003
Posts: 305
Likes: 0
From: Penn Valley
Let me reinforce the real answer here, because I deal with these things all the time, and I have even adapted one to my old 6.9, and had to figure out the operation for that.
The light is not on a timer but it might as well be. The controller senses the current drawn by the glow plugs and turns out the light when the current drops below a certain level, meaning they are hot. Since they cool off pretty much immediately when you shut off the engine, you will get a fairly long wait light each time you go to start even if the engine is warmed up.
The controller is easily fooled by bad glow plugs or bad wiring, which it sees as low current draw, meaing already hot glow plugs, and does not hold the light on for long. Many people have discovered that watching the voltmeter instead of the light will allow them to leave the malfunctioning system on for the longest period possible and the truck will still start.
This is in contrast to the old 6.9 system which sensed engine temperature instead of glow plug temperature, and would not give a wait light at all if the engine was already hot.
Birken
The light is not on a timer but it might as well be. The controller senses the current drawn by the glow plugs and turns out the light when the current drops below a certain level, meaning they are hot. Since they cool off pretty much immediately when you shut off the engine, you will get a fairly long wait light each time you go to start even if the engine is warmed up.
The controller is easily fooled by bad glow plugs or bad wiring, which it sees as low current draw, meaing already hot glow plugs, and does not hold the light on for long. Many people have discovered that watching the voltmeter instead of the light will allow them to leave the malfunctioning system on for the longest period possible and the truck will still start.
This is in contrast to the old 6.9 system which sensed engine temperature instead of glow plug temperature, and would not give a wait light at all if the engine was already hot.
Birken
Junior User
Joined: Oct 2003
Posts: 75
Likes: 0
Pnose- read my whole original post- all I was saying is that watching that light is not the best way to get the truck started- If a newbie cranks as soon as his WTS light flashes off it will start hard. He or She would not know the difference in the burn time of the light is long or short and if they had a manual they would not be asking the question in the first place- so how long it remains on is greek to them in the first place. It would just start harder unnecessarily when if they watched the gauge it would start easier.
I could give a rat's a$$ what you do- but IF YOU WANT TO KNOW WHEN YOUR PLUGS ARE BURNING YOU HAVE TO LISTEN TO THE RELAY/ Watch the gauge that was the message I was conveying.
And CRMW quote this:
If your gauge bounces up the same time the wait to start light goes off, chances are you have some glow plugs out-
I Know what you have been trying to tell me I didn't all along. You took what I said incorrectly- if you read the whole post it makes more sense, if anything it is my fault for not being more clear-
but in conclusion, again, IF YOU WANT TO KNOW WHEN YOUR PLUGS ARE BURNING YOU HAVE TO LISTEN TO THE RELAY/ Watch the gauge
That's the last time I am touching this.
I could give a rat's a$$ what you do- but IF YOU WANT TO KNOW WHEN YOUR PLUGS ARE BURNING YOU HAVE TO LISTEN TO THE RELAY/ Watch the gauge that was the message I was conveying.
And CRMW quote this:
If your gauge bounces up the same time the wait to start light goes off, chances are you have some glow plugs out-
I Know what you have been trying to tell me I didn't all along. You took what I said incorrectly- if you read the whole post it makes more sense, if anything it is my fault for not being more clear-
but in conclusion, again, IF YOU WANT TO KNOW WHEN YOUR PLUGS ARE BURNING YOU HAVE TO LISTEN TO THE RELAY/ Watch the gauge
That's the last time I am touching this.
Freshman User
Joined: Jan 2004
Posts: 44
Likes: 0
From: Upstate NY
Wow, C'mon people. We all have opinions on everything, from toilet paper to steak sauce. Just absorb what you want and flush the rest. There are more people online that are full of it than I ever thought possible, but there are also others online that know more than 15 dealer mechanics combined and are more than willling to offer said knowledge for free if you ask the right questions. Sometimes you just have to sift through the B.S. to get what you want, just like the presidential campaign.
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 16
From: Nutter Fort, WV
Bad thing is you can not tell if you do not know any different.
Ask 10 people something and get 8 different answers.
I just say and do what works for me.
Are you gonna vote for me in the next election if I run against Bush?
Ask 10 people something and get 8 different answers.
I just say and do what works for me.
Are you gonna vote for me in the next election if I run against Bush?
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