Engine/Transmission (1998.5 - 2002) High idle at cold startup?

[DirtyDodge]

Hello,



I started my truck this morning at 10 deg F temp and walked back into my house. After a minute or so, I noticed the truck getting loud. I walked back out and seen the idle at 1100+ RPMs. Is this a programmed feature of Dodge, is this not normal. I don't really want it to do this since the oil temp is still low. I would rather it lope along until temps increase. I notice that if I hit the brake or put it into gear, it drops back to its normal idle rpm. After 1 minute or so, it will repeat and raise back to 1100 rpms or so. The only real after market mod (BOMB) I have is the Catcher software, the rest of the mods in my signiture are minor. I did not have the heater plugged in either. I know I should but forgot. Anyway, please help.



Thanks,

Derek

 

[benhall]

What you experienced was the Cold Idle feature that is built into our ECU's. This feature is designed to warm the motor up and prevent damage to internal components, but if I remember right the component they (DC & Cummins) were targeting were the pushrods. Our pushrods are prone to sticking when they are cold and are lacking lubrication, so the idle comes up to increase the oil flow and add a little bit of a load to the motor to help in this warm up. Also, when the temp goes even lower, 3 cylinders will shut down and become "dead weight". This feature increases the load and aids in the warm up process. I had to have both of these features enabled when I got back from Germany and they work very well. I would leave this feature on if I were you, as you will be happy that you did. If you have any questions on it, just ask away. There is also more reading on this subject in here.



Ben

 

[Nate]

I downloaded that Software for the Smarty, but it doesn't work on my truck for some reason. It was ~25* this morning, so I fired it up about 10 mintues before I left. Idle never changed.

 

[PKozlowski]

Totally normal. Just wait till it goes into 3 cylinder idle mode!

LOL! You'll like that.

 

[JKinney]

Dirty Dodge, Your lucky it works. I wanted mine to work a couple years ago and the dealer wanted $100. 00 to make it work. I bought smarty and now ive got it





Nate Mine will work at that temp, funny how I can go skiing all day and come out to the parking lot a 9 pm and the engine is not cooled down enough to work, even though the out side temp was reading in the teens. Have you taken your smarty back to stock? and then reload your smarty # you wish to use? Im just guessing but that might do it.

 

[DirtyDodge]

How cold does it have to be for 3 cylindar mode? I think it may have been on this mode? Does it almost sound like a knocking noise? May have been on this morning?

 

[PKozlowski]

Ya, knocking sound. it will idle normally, then go to high idle then to 3 cylinders

and you'll really notice it. Almost sounds like it's going to come apart! LOL!!

 

[DirtyDodge]

okay, thanks for all your replies. I thought for sure something was wrong. Glad I have this sight as a resource.

 

[JKinney]

How cold does it have to be for 3 cylindar mode? I think it may have been on this mode? Does it almost sound like a knocking noise? May have been on this morning?

I have never been there as my rig is stored in a semi heated garage, but I think around 0 deg or so... .

 

[benhall]

The 3 cyl feature will kick in around 15 degrees, give or take a few. The first time you hear it will scare you.



Ben

 

[PKozlowski]

Tell me about it, My dog was outside with me the first time it did that and he took off running. LOL!! I was personally thinking of joining him.

 

[SnoKing]

Dodge/Cummins is concerned at valves sticking and bending the push rods if the engine idles too long in really cool weather. I have been working in the garage finishing the walls etc, so my truck has been setting outside in the low 20's.



If you want quick warm up, fast idle and an exhaust brake will get my truck up to 140 degrees in about 5 minutes. I actually wish the Banks exhaust brake would stay on past 140 degrees, but the is the temp in the Banks computer.



Truck can set out in the mountains all day while we snowmobile and fast idle will not work as sameone above pointed out.



Now the bad combination. Exhaust Brake and 3 cylinder idle! Engine died! So I have to leave the brake off if it is cold enough for 3 cylinder idle. After warming up past the 3 cylinder period, I can then turn on the brake.



BTW, I have the power for the DTT smart controller and Banks brake on an old style headlight switch on the floor. Works really good with an auto. Gives your left foot something to do once in a while. I have the 3rd to OD speed set at around 48 MPH (55 when towing) right now and it I what to go to OD below that I can click off the power to the DTT controller with my left foot. Also I am not using the exhaust brake on the icy roads right now when in two wheel drive. In four wheel drive it would be OK, as the front and rear would be tied together. SNOKING

 

[DirtyDodge]

The 3 cyl feature will kick in around 15 degrees, give or take a few. The first time you hear it will scare you.



Ben

When it was knocking like it was (3 cyl mode), I thought my engine was about to throw a rod. I ran out of the house and hit the brake, everything sounded normal. That's when I decide to check with you guys. I plugged it in last night, no high idle at start up, no glow plugs, it started like any other day even though it was 7 degrees this morning. Brought an extension cord to work today too, so it will start alot easier when I get off tonight.



Take it easy,

Derek

 

[Nate]

I hope you don't have glow plugs

 

[Bob Wagner]

worked perfect this morning. perfect

 

[chazj]

I've had my truck down to around 10 below 0 in Minnesota. It always started "right off the bat" with but one cycle of the grid heaters. That said... am curious as to why I've never experienced " 3 cyl. mode or a fast idle". Even this morning at 11 degrees in Carson City it just started as though it were much warmer.



This feature is noted in my operator's manual so I thought it was "standard. " Hate to go pay the dealer to check this out but maybe that's the only way to have it operational???

 

[DirtyDodge]

I hope you don't have glow plugs

I'll re-phrase; no "wait to start" light

 

[DMcLeod]

my experience: On Thanksgiving day it was -20F, and the truck cold soaked for about 12 hours. I started it up and turned the Jacobs exhaust brake on. The engine did the high idle and the 3-cylinder tricks while the exhaust brake was on and warmed up to 140F in about 10 minutes.



Also, while idling at colder temps, the engine WILL return to high idle when the sensors reach the set limits. I've left the truck idling at -40F :--) while getting groceries and when I returned it was on high idle.

 

[SNiebaum]

My truck just kicked up the high idle as I type... 22 degrees and snow on the way... .

 

[16919]

Does the parking brake count as canceling out the high idle as I have a 6sp?