I have read about the 08's with a high idle switch, where is this located?

It's not a physical switch, idle speed can be adjusted using the cruise control functions. It operates similar to the classic models (LB7 - LLYs) with the PTO modification...

You can turn it on ond off through the DIC My 07 did not have that option but the 08 Does

hmm i thought all have had taht funtcion except didn't have the ability to idle it up or down.

Can this be added to an 07 LMM ?
My truck may sit and idle for an hour or 2 at a time.

Whats the recommended rpm for extended idle ?

Mine says high Idle > on > off on the DIC but I cannot change the speed with the cruise controls or any controls , unless I am doing something wrong?

seems that there is only the two positions and the computer determines the high idle by temps if on is chosen ! ?? t

To turn on the high idle, you use the bottom left side cruise button. To set a desired speed, use the foot pedal to raise the engine rpms to your desired level, and push the upper cruise button on the left...

The parking brake has to be on and the cruise also hase to be on.

I have also found on a cold engine, the high idle does not work. it needs to be a certain temp on my truck... Not to far away from cold, but not right after start up.

I tried the cruise the way You said and it does not change the idle

same here. Maybe it only works with 08's with the high idle switch.

I did have the high idle option on my truck.

I am pretty sure for this to work GM makes you pay $200.00.....

I am unsure if anyone has had it programed or found the wires thay need to connect up?

my buddy has an 07.5 and it has the high idle option on the dic

my buddy has an 07.5 and it has the high idle option on the dic

Just picked up my 07.5 today. No high idle in the DIC. But there was a wonderful note in the owners manual about turning the truck on and stepping on the gas, then stepping on the brakes within 8 secs. and then something else.........-:t

I think there is a little confusion going on here...

The high idle that can be activated in the DIC is to help warm up the engine when the ambient temp is below 32 degrees. That feature has been available since at least '06. If you don't have a DIC (tee hee :D) you can activate it using the accelerator, brake pedals, rubbing your head while patting your belly, but only during nights with a full moon (maybe not all those steps, but nearly as mind numbingly stupid to be sure).

The high idle "switch" is only on the '08s as an option, (only $200 :eek:) and with it you can set the engine rpms to any speed using the cruise control switches on the steering wheel, at any time, not just when its cold outside.

Hope this clears up what the "switch" really does....

That's what I thought but I went through all the settings in the DIC and did not see the high idle option. I'll check again.
Does anyone know if there is a software upgrade for it?

Turn the key on ( not start) > push accelerator to the floor and hold while tapping the brake pedal on and off 5 times within 8 seconds > the DIC will say high idle off or on change it with the DIC lower button !

Can the adjustable version be added at the dealer and is it still $200 and wat is envolved ? t

Im getting a new 08 and working with dealer they told me all 08 have this is this so or smoke if so why is this an option

I need to prove this to a dealer is there a site I can go to with this info

See my post above about the confusion. The dealer is correct in saying that all '08's have the high idle feature that increases the idle speed when the ambient temperature is below 32 degrees. If you want the high idle "switch" that allows adjusting the idle speed at any time using the cruise control switches you have to order option UF-3.

Tell your dealer to read his flippin' print book... it's all explained there.

You can also download the print book for yourself here: http://eogld.ecomm.gm.com/NASApp/domestic/vehiclesel.jsp?year=2008&regionID=1&divisionID=2

Click "printbook" and select the sections that you want. It lists every single option and code that you can order.

HTH

Mike

In the DIC it is called elevated idle. When this mode is on the engine will idle at a higher RPM when the ambient temp is cold. Once the coolant temperature reaches a certain point it will idle back to normal RPM. This is only to help the engine warm faster.

The high idle 'switch' (as in your traditional high idle switch) is a $200 option that allows you to put the engine in a high idle mode and adjust the RPM using the cruise control.

thanks for the ammo

think it's getting real deep in here guys!

think it's getting real deep in here guys!

As in....???

My '08 LT2 has it in the DIC and the BOOK clearly explains how to use it.

Turn it on in DIC, parking brake on, cruise UP button.

Just picked up my 07.5 today. No high idle in the DIC. But there was a wonderful note in the owners manual about turning the truck on and stepping on the gas, then stepping on the brakes within 8 secs. and then something else.........-:t

As in....???

nothing in my DIC either! Lights, mirrors, tires, memory seats blah blah..not idle! That's what I mean!

The new Lmm's have this but only when first started to help warm up quickly it is called Elevated Idle. this will change the idle from base to 1050 RPMs. to activate this The engine must be off with the key on Run. Press the Accelerator pedal to the floor and hold while quickly pressing the brake pedal three times in less than eight sec. release the accelerator and start the engine. if u did it right the dic will tell u ELEVATED IDLE ON or visa versa. do the same to turn it off. but remember this only works when it is 32*F or below now on the new 08's i wasnt sure about this option so i asked my dealer and he said "yeah that will cost ya about $250 with taxes. what it is, is a system that will allow u to turn the idle up only in park by ur Cruise control system. but as soon as u hit ur brake or move you Auto Shifter the system shuts off. if u ask me it sounds like its worth the $250

The new Lmm's have this but only when first started to help warm up quickly it is called Elevated Idle. this will change the idle from base to 1050 RPMs. to activate this The engine must be off with the key on Run. Press the Accelerator pedal to the floor and hold while quickly pressing the brake pedal three times in less than eight sec. release the accelerator and start the engine. if u did it right the dic will tell u ELEVATED IDLE ON or visa versa. do the same to turn it off. but remember this only works when it is 32*F or below now on the new 08's i wasnt sure about this option so i asked my dealer and he said "yeah that will cost ya about $250 with taxes. what it is, is a system that will allow u to turn the idle up only in park by ur Cruise control system. but as soon as u hit ur brake or move you Auto Shifter the system shuts off. if u ask me it sounds like its worth the $250It's all described in the owner's manual somewhere. On an 08 LMM there's elevated idle that can be set on or off in the DIC - it works when you start the truck and temps are low - elevated idle to about 1,050 when in park, once you shift idle returns to normal. I know this works since we had a pretty cold morning in Denver earlier in the week. Additionally, there is a $200 option that allows you to control the idle via the cruise control buttons no matter what the temp - haven't tried this one yet. I think it's RPO UF3 and it's called High Idle Switch.

My buddy is a tech at a Gm dealer up here in canada and he told me GM is voiding warrentees if you idle your vehical alot. He said two tow trucks which idle alot where void they just plug into your puter and it will give them the info they need. Now this in 08's must have something to do with the emmisions and crap, maybe why GM is now offering it as an option

Mr big block Does your buddy know if this manual high idle through the cruisr control option can be turned on in the 07.5 lmm thanks.

High idle seems to turn on by itself when cold. Started my truck today and it was 33 degrees this morning. It went to a real high idle for a few minutes and then dropped?

Duramax lover i will let you know when i see him next just got my 05 back from the shop.

yeah hope you can,as this would be nice here in alberta thanks

nothing in my DIC either! Lights, mirrors, tires, memory seats blah blah..not idle! That's what I mean!

Doesn't your DIC have this screen?

If not then something's wrong, or you have to set it using the accelerator and brake pedals as indicated in your owner's manual (You have read it, haven't you?) THE IDLE IS ONLY RAISED WHEN THE AMBIENT TEMPERATURE IS <32 DEGREES WITH THIS SETTING. IT DOESN'T WORK AT ANY OTHER TIME AND IS MEANT TO HELP WARM UP THE ENGINE WHEN ITS COLD!

Also, since you don't have an '08, then you can't and don't have the high idle switch option that allows you to set the idle anytime / any temperature. That's all there is to it...:D

And if you DO have an '08 with the high idle switch option, then this is what your DIC says when it's set...

[quote=Shasta;2095195]Doesn't your DIC have this screen?

If not then something's wrong, or you have to set it using the accelerator and brake pedals as indicated in your owner's manual (You have read it, haven't you?) THE IDLE IS ONLY RAISED WHEN THE AMBIENT TEMPERATURE IS <32 DEGREES WITH THIS SETTING. IT DOESN'T WORK AT ANY OTHER TIME AND IS MEANT TO HELP WARM UP THE ENGINE WHEN ITS COLD!

Also, since you don't have an '08, then you can't and don't have the high idle switch option that allows you to set the idle anytime / any temperature. That's all there is to it...:D[/quote

Thats is why it came on the other morning? I was fooling around a month or so go and seen (high idle on) come on the dash but it never did aything until the other morning.

Thats is why it came on the other morning? I was fooling around a month or so go and seen (high idle on) come on the dash but it never did aything until the other morning.

You got it! I've been working in the NM mountains where its been pretty chilly in the morning, and it has come on the last few days...

I bought the $200 High Idle "switch". For that kind of money, I want a real switch; not some lousy software upgrade dammit! :mad:
This is a scam.

I bought the $200 High Idle "switch". For that kind of money, I want a real switch; not some lousy software upgrade dammit! :mad:
This is a scam.

Well apparently we both fell for it, and there's more than a few others that wished that they had...:rolleyes:

I bought the $200 High Idle "switch". For that kind of money, I want a real switch; not some lousy software upgrade dammit! :mad:
This is a scam.

I wonder what would happen if, say, you were able to get an ECU dump from someone that had that option. Then try to program that into a truck that didn't come with the option.

All for testing/verification purposes, of course ;)

Doesn't your DIC have this screen?

If not then something's wrong, or you have to set it using the accelerator and brake pedals as indicated in your owner's manual (You have read it, haven't you?) THE IDLE IS ONLY RAISED WHEN THE AMBIENT TEMPERATURE IS <32 DEGREES WITH THIS SETTING. IT DOESN'T WORK AT ANY OTHER TIME AND IS MEANT TO HELP WARM UP THE ENGINE WHEN ITS COLD!

Also, since you don't have an '08, then you can't and don't have the high idle switch option that allows you to set the idle anytime / any temperature. That's all there is to it...:D

Sure don't!! I'll do some research and letcha know. Thanks for the pic!!