Cold start + Idle time?

[RIDGERACING]

New Owner and member! I was always under the conseption that diesels were alright to idle for hours with no harm other than wasted fuel. Can I let my truck idle for 10-60min with no harm? At the same time I like to warm my truck up in the morning for 10-20min. before I go to work for a 30mi. drive. Is it ok as well to let it warm up for that time,2nd should I have my dealer bump the idle up when it is sitting idle for a certain time or when it is cold out. I did notice 1 time when I went out to my truck in the morning and the idle was about 200rpm higher until I pressed on brake to engage trans. It was especialy cold that morning 20deg or so. Thanks for your input

P. S I love the truck except for the bad fuel millage. 12. 8mpg 1st tank!!

 

[JayWm]

Congrats on the new truck, and WELCOME to TDR. When you have a chance, fill in your signature w/ your truck info as we find this is helpful to other members.



There has been a lot of discussion about idle time. There is some concern that idling for long periods can allow the engine to cool off to the point that cylinder washdown can occur. You can use the search feature to find old threads and you decide how long you want to idle for. Diesels don't build much engine heat when idling, so cold start ups and idling won't gain you a lot of heat. Using the high idle function if you have it will get it to warm up. Others have installed exhaust brakes and will idle against the brake to warm the truck. You can also plug in the block heater overnight. All depends on your needs and how cold it gets at night for you. Sounds like it gets cold at night where you are. The engine on these trucks will slowly raise idle to 1000rpm under certain conditions. One of them being air temps below 32 degrees. Where I live it does not get real cold at night so I don't use the block heater, I will let the truck idle for a few minutes and then I pull out and drive real easy for the first several miles until the temps come up to normal.



For you since the high idle kicked in on its own, I'd get the dealer to enable the high idle feature. This allows you to use the cruise control buttons to raise idle speed manually when you like. The automatic version only does it when certain conditions are met.

 

[macdaddy]

I'm on my second CTD. Never have let either truck idle longer than it takes to get good oil pressure. Start it wait for adequate oil pressure and avoid full throttle till she warms up and your good to go .



Prolonged idling promotes fuel dilution in your crankcase, and lead to injector fouling.



Mac

 

[GWBourne]

personaly i TRY to stay under 1800rpm when driving on first start up of the day till its warmed up.



i also dont let it lag at all when it is cold.



but i beat the **** out of it once it is warm... .



welcome to TDR

Grant

 

[GAllen]

I agree with GWBourne and macdaddy..... get the oil pressure stabilized, possibly a minute or two and get going, easy on the throttle. My high idle will go to 1500 rpm for warm up and I can drive the truck down the street and keep it under that, so why not be moving while it's warming up. When doing this I get the temp gauge to move with in a couple of miles or about 3 minutes. That'll never happen that quickly in the driveway.

 

[TSPowell]

Congrats on the new truck, and WELCOME to TDR. When you have a chance, fill in your signature w/ your truck info as we find this is helpful to other members.



There has been a lot of discussion about idle time. There is some concern that idling for long periods can allow the engine to cool off to the point that cylinder washdown can occur. You can use the search feature to find old threads and you decide how long you want to idle for. Diesels don't build much engine heat when idling, so cold start ups and idling won't gain you a lot of heat. Using the high idle function if you have it will get it to warm up. Others have installed exhaust brakes and will idle against the brake to warm the truck. You can also plug in the block heater overnight. All depends on your needs and how cold it gets at night for you. Sounds like it gets cold at night where you are. The engine on these trucks will slowly raise idle to 1000rpm under certain conditions. One of them being air temps below 32 degrees. Where I live it does not get real cold at night so I don't use the block heater, I will let the truck idle for a few minutes and then I pull out and drive real easy for the first several miles until the temps come up to normal.



For you since the high idle kicked in on its own, I'd get the dealer to enable the high idle feature. This allows you to use the cruise control buttons to raise idle speed manually when you like. The automatic version only does it when certain conditions are met.

I was messing around one morning with my cruise control and raised the rpm's, don't know exactly what I did but couldn't seem to do it again. I guess my high idle option has been turned on. You said there are certain conditions that must be met, what are they. I was thinking about buying a high idle mechanism, but know it sounds like I can save the money, If I can figure out what I did the first time. I wanted to set the idle at 1500 rpm. Sound reasonable? Its always around 0 or below here.

 

[99Supercab]

To turn on the manuel high idle feature, do this :



Start truck

Turn Cruise control on

Press the Set button



Idle will jump up to about 1,000 RPM`s, from there, you can use the resume/accelerate button to run the idle up to 1,500 RPM`s or anywhere in between.



To turn off the high idle, simply press the Cancel button on press the brake.



Enjoy.

 

[Giachino]

It doesnt get too cold here in So Cal so I just idle for a minute or two, and drive easy for a couple of miles... . I find that letting it idle too long tends to gum up the injectors (based on drivability, not checking the actual injectors). High Idle feature is free, no need to spend money for an aftermarket add on.

 

[RIDGERACING]

I tried this and it did not work? The only time I noticed my idle bumped up was one time when it was in the low 20s after starting it up in the morning. I went out to start it and 20 min later I went to pull out and noticed it was 2-300rpms higher till I engaged brake to put it into drive. I would like to bump up the idle in cold mornings before leaving for 5-10min. or so.

 

[jcroman]

i hooked my high idle. to my remote start. after it starts it waits 10 seconds for engine to stabalize then it turns the cruise on and sets it. it goes to about 1100 rpms. then i have my auxillaray channel set to raise the rpms 100 every time i hit the button up to 1500rpm's. It is all done thru differnt size resisters since all the cruise controls are done using only 1 wire!!!!. it took me a while to figure out the right sizes. it works awsome. if anyone would like to know what resisters to use and how to do it let me know.

jamie

 

[jcroman]

I tried this and it did not work? The only time I noticed my idle bumped up was one time when it was in the low 20s after starting it up in the morning. I went out to start it and 20 min later I went to pull out and noticed it was 2-300rpms higher till I engaged brake to put it into drive. I would like to bump up the idle in cold mornings before leaving for 5-10min. or so.

if it didnt work you need to take it to the dealer to get it enabled.

 

[BrianJ]

I tried this and it did not work? The only time I noticed my idle bumped up was one time when it was in the low 20s after starting it up in the morning. I went out to start it and 20 min later I went to pull out and noticed it was 2-300rpms higher till I engaged brake to put it into drive. I would like to bump up the idle in cold mornings before leaving for 5-10min. or so.

There are two distinctly different high idle features for the CTD.



The first in an automatic high idle that will take the RPM to appx 1000 in temps below 32 degrees until the engine reaches a certain operating temperature. This will turn on one minute AFTER you last touch the brake pedal, clutch, or throttle, and will turn off as soon as you hit one of the same. Again, this is automatic and only occurs within certain ambient and operating temperatures.



The second high idle feature is a manual process and has to be enabled by your dealer using their scan tool (simple process, and they should do it for free). Once enabled you can use the cruise control buttons to idle up to 1500 rpm's.



If you want the truck to warm up faster get an e-brake, as mentioned previously. I can warm it up as much as twice as fast.



Happy trucking, and welcome aboard...

 

[BrianJ]

Additionally, I would not let the truck idle more than 10 or so minutes at the risk of fouling the injectors.

 

[JCleary]

I start my truck and let it run for 1 minute. That's enough time for oil to circulate. Then I drive it easy (under 2k rpm) until it's warm. Then, flog it!

 

[Poulsen]

I fire mine up - head in to the house, pour my coffee, put my coat on and out I go - takes maybe 5 minutes.....