I started my 05 this morning and went back in the house to let it warm up some. I can hear it when the grids kick in and out, anyway after the grids where done it went to high idle all on it's own. Is this stock feature? So I get in truck and give accelator a tap like you would a carborator gas eng and it idles down so then I back out and set in the drive and it starts high idle again. Anyway I drive about 60 miles to pick up a load of pipe and while I am being loaded it goes into high idle again. The nose is pointed to the north and it's cold about 32 and I had been setting about 10-15 min. When I got back to truck it had idled back down.I am still suspicious that this truck my have a programmer. Is all what I am experincing normal (stock)

My 03 did the same thing. I think you can manually adjust it up and down with the cruise buttons on an 05 too.

Perfectly normal. ~32° and lower it will go to 1,000 rpms after 2 minutes; ~15° and lower it goes to 1,000 as soon as you start it. Then if the ambient is lower than 32° and your coolant is below 180° it will do it again after 2 minutes of stationary time. You don't want to interrupt this, it's a feature that helps the motor stay warm to prevent cylinder washing. Really you shouldn't be idling your truck before it's warm anyways, it's much harder on the motor than driving easy until the coolant is warm. The best thing to do is to fire it up, let it idle about 30 seconds to build oil pressure and drive easy. If you want heat sooner use the block heater. Yes 05's can also use the cruise control to adjust the idle. Smarty will enable this, as will the dealership and other tuners. With the truck in P turn the cruise control on, then press set. RPMs should go to 1100. Then use accel/decel to go up/down between 1,100 and 1,500 in 100 rpm increments. I use this feature all the time, to cool the motor after towing, increase load when idling in the cold, or provide more heat if I need to leave a kid in the truck in the cold.

I guess I really need to read my manual:doh:

Perfectly normal. ~32° and lower it will go to 1,000 rpms after 2 minutes; ~15° and lower it goes to 1,000 as soon as you start it. Then if the ambient is lower than 32° and your coolant is below 180° it will do it again after 2 minutes of stationary time.

You don't want to interrupt this, it's a feature that helps the motor stay warm to prevent cylinder washing. Really you shouldn't be idling your truck before it's warm anyways, it's much harder on the motor than driving easy until the coolant is warm. The best thing to do is to fire it up, let it idle about 30 seconds to build oil pressure and drive easy. If you want heat sooner use the block heater.

Yes 05's can also use the cruise control to adjust the idle. Smarty will enable this, as will the dealership and other tuners. With the truck in P turn the cruise control on, then press set. RPMs should go to 1100. Then use accel/decel to go up/down between 1,100 and 1,500 in 100 rpm increments. I use this feature all the time, to cool the motor after towing, increase load when idling in the cold, or provide more heat if I need to leave a kid in the truck in the cold.

How cold is it ok to do this? I nearly always plug it in when it gets cold but sometimes it just doesn't work out. Like sometimes it'll be as cold as 10 without being plugged in. It sure rattles if I start driving at that temp.

His is a 3rd gen and your second gen probably ahsnt had the high idle enabled. You can get the dealer to load it or hook up a smarty. Mike has the TSB to take to your dealer somewhere around here.

I have the fast idle activated on my truck. I'm just wondering about the 'not good to idle til it's warm part' If it's -20 should I just go ahead and drive or let it idle for a while?

Like for me I might let it idle for enough temp to bring coolant temp up to 80-100*F and then leave by that time everything in the engine is well lubed up and the oil is starting to thin down a bit and more than safe to drive. By 140-160*F you can cut loose and kick that pig...

This Caution not temp specific, and refers to low idle.

Do not idle the engine for excessively long periods. Long periods of idling, more than 10 minutes, can cause poor engine performance.

Do not operate engine at low idle for long periods with engine coolant temperature below the minimum specification in Maintenance Specifications (Section V). This can result in the following:

[*]Fuel Dilution of the lubricating oil

[*]Carbon build up in the cylinder

[*]Cylinder head valve sticking

[*]Reduced performance

Minimum Recommended Operating Temperature 71°C [160°F]

As temp drops the coolant temp really drops (or stays low) at low idle.

2-3 minutes of idling is fine as the grid heater is keeping intake air temps up, which improves combustion.

my 05 idels up by itself and i can also raise the idle with cruise even with a manual trans. i love this feature.

Just for information, my 03 does not this feature according to the dealer tech.They did say this feature is only available with a steering wheel that has the buttons on top of cross bar itself "Flush" and not recessed lower between them.

What is the best way to warm up my pickup. I live at an apt and don't have the ability to plug in. I have the high idle. Is it better to let it warm up by itself or can I engage the high idle manually right away?

I would start it, let it idle for a few seconds and drive it easy until its warm. If your scraping windows then fast idle it. But don't just let it idle to warm up, it's hard on a motor.

I personnaly think the best way to warm it up is to drive it. I start mine and let it idle for 20 to 30 secoonds and drive easy untill I see either temp going up or oil pressure dropping. Usually happens in 5 miles or so. Thats my 02, not sure if it works any differant for a 3rd gen

I would start it, let it idle for a few seconds and drive it easy until its warm.

If your scraping windows then fast idle it.

But don't just let it idle to warm up, it's hard on a motor.

Is it hard on any motor or just these cummins? Just thinking about my days of truck driving and there's guys out there that are pretty fanatical about idling their big rigs till 120* or even higher before even starting to drive easy.

Is it hard on any motor or just these cummins? Just thinking about my days of truck driving and there's guys out there that are pretty fanatical about idling their big rigs till 120* or even higher before even starting to drive easy.

It's hard on any diesel, there are Cat, Detroit, and Cummins bulletins about it. Min temp for full load is 160°, so use that as a guide.

Let me start by saying I plug my truck in if I know it is going to be below 40 at night. On a really cold morning I will start it about 5 minutes before I leave to help defrost. Is this good or bad? --- I am here: http://tapatalk.com/map.php?i42ulp

If you need the defrost it's one thing, but an ice scraper and driving would be better, IMHO.

Without some sort of virtual loading Cummins diesel engines don't produce much heat. Idling a engine is all that great. But if you have a exhaust brake and/or high idle abilities then you got a different story. But for me to just start my truck and idle it will take a very long time to warm up and its not suggested. The problem is Cummins diesel engine are not ment to be operated at coolant temps below about 170*F. So high idle feature was designed by Cummins but disabled by Dodge.

I usually do the scrapper but every so often I will do the 5 minute idle when it is extremely cold and frosted up. --- I am here: http://tapatalk.com/map.php?w0eerm