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Discussion Starter #1
I head out to work early, round 5:30am and its has started to dip down in temp here lately, low 50's, high 40's. I have noticed a few times in the morning that the truck starts up just fine but after 30-45 seconds of idling, the idle will raise up by itself from 650-700 to about 900-950. When I put the truck in gear, it drops to the normal idle of 650. Is this the "Cold-Elevated Idle"?

Also, this is my first diesel but I have always heard about warming the glow-plug and I would assume the LML is no different. I don't see any kind of glow-plug indicator light on our dash though. My brother has an 07 F250 and he has a light that goes off when his glow plug is warm and ready to start. Do we have one too?
 

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yes sir thats what that is goes to almost 1300 when really cold, and yes u do have a glow plug indicator , mine stays on for like 1 sec or so its fast, unless the lml came with a diff system
 

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yep completely normal
 

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Yours isnt going into Elevated Idle. Elevated Idle comes on when its below 32 degrees F and the engine coolant temperature is below 150 degrees F.
 

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hmm i dont think it should be coming on at low 50's or high 40's though, its got down into the 30's here and mine still hasnt kicked on yet
 

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Elevated Idle
The engine has a cold temperature
high idle feature which elevates the
engine idle speed from base idle
to 1050 rpm for pickup models or
1200 rpm for van models when
outside temperatures are below 0°C
(32°F), and the engine coolant
temperature is below 65°C (150°F).
This feature enhances heater
performance by raising the engine
coolant temperature faster.
This feature can be turned on or off
using the DIC buttons. If the vehicle
is not equipped with DIC buttons, do
the following to turn this feature on
or off:
1. Turn the ignition to ON/RUN,
with the vehicle off.
2. Press the accelerator pedal
to the floor and hold while
quickly pressing the brake
pedal three times in less than
eight seconds.
3. Release the accelerator pedal
and start the engine.
When the engine is started, it will
slowly ramp up to the high idle
speed after a delay of a few
seconds up to approximately
two minutes. For this method to
work properly there must be no
throttle or brake pedal faults.
The engine idle speed will return to
normal once the following conditions
are met:
. Once engine coolant
temperature reaches
65°C (150°F).
. Air intake temperature reaches
0°C (32°F).
The high idle speed will be
temporarily interrupted and the
engine speed will return to normal
if any of the following conditions
occur:
. The brake pedal is applied.
. The accelerator pedal is
pressed.
. The transmission is shifted out
of P (Park) or N (Neutral).
. Vehicle speed is detected.
Once these inputs are removed, the
engine idle speed will slowly ramp
back up to high idle after the normal
delay, if the conditions for engine
coolant temperature and air intake
temperature are still met.
 

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Your glow plug indicator looks like a horizontal spring and should be in the tach area of your gauge cluster.

And my LML also runs a slightly higher idle when starting up since it has started getting colder. Not as high as the "cold elevated idle", but like you say in the 900 range.
 

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Your glow plug indicator looks like a horizontal spring and should be in the tach area of your gauge cluster.

And my LML also runs a slightly higher idle when starting up since it has started getting colder. Not as high as the "cold elevated idle", but like you say in the 900 range.
Mine did not idle at higher last winter unless is was in 'elevated idle'. Are you sure the 900 range idle is not because it's in regen?
 

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I'm sure. Turn the truck on in the driveway, engine starts then idles up to 900. As soon as I put it in reverse drops right back down to 600.
 

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Mine does that too. It will not drop down to 600 with the application of the brake pedal. I must shift to get it to drop down. It is not a regen idle. If it is not a true elevated cold idle, it must be a slightly elevated idle for emissions or something. It has not been cold enough here to meet the parameters required for a true elevated idle.
 

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Discussion Starter #11
Okay so now the truck is doing something different. I run my tank to empty before refilling to monitor my fuel milage and when the tank gets low (<80 miles on Distance Till Empty) the idle will raise up both in park and drive and its staying up even when the truck is hot and I've been driving for 20 minutes. It's been warm here for October; 60's - 80's. When it was the 'cold-elevated idle" it was raising to 950 or so and then dropping back down when I put it in in gear. This is not as high of an idle but it does not drop off. Here's the progression:

Start vehicle, in-park idle around 600.
20 - 30 seconds later, in-park idle raises to around 800
Put the truck in gear, idle remains at 800
Vehicle is hot, idle remains at 800

When I fill the truck up, it stops. Is this normal?
 

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Okay so now the truck is doing something different. I run my tank to empty before refilling to monitor my fuel milage and when the tank gets low (<80 miles on Distance Till Empty) the idle will raise up both in park and drive and its staying up even when the truck is hot and I've been driving for 20 minutes. It's been warm here for October; 60's - 80's. When it was the 'cold-elevated idle" it was raising to 950 or so and then dropping back down when I put it in in gear. This is not as high of an idle but it does not drop off. Here's the progression:

Start vehicle, in-park idle around 600.
20 - 30 seconds later, in-park idle raises to around 800
Put the truck in gear, idle remains at 800
Vehicle is hot, idle remains at 800

When I fill the truck up, it stops. Is this normal?
Sounds like it was doing a regen, wich will raise the idle to 900rpm, regen lasts 20-30 minutes. When you filled up it probalbly finished regen and coincidently idle returned to normal.
 

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Discussion Starter #14
+1, that's what it sounds like to me.
It was a regen, stopped when I got in the truck yesterday. Love your signature Nginear, by the way.
 

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i dont think mine works
 
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