Cold Start

[bzingre]

Went out to start the truck this morning, it was about 18F. I didn't have it plugged in. I turned the key, let the inlet heater do its thing. I bumped the starter, engine turned over about 3 times and fired. But the problem is that it didn't start running at the normal 750 rpm, it immediately started to run at 1000rpm. Is this normal? The other day when it was 21F and I started it, the engine idled at 750rpm for about 2 minutes and then it bumped itself up to 1000rpm. I didn't have it plugged in then either. I don't like the fact that it runs at 1000rpm right off the bat because there is no oil pressure and it's hard on components to run fast when they are cold. So, any input would be great.

 

[lschultz]

Thats normal just the fast idle kicking in. Hasn't been cold enough down here yet for that to kick in. It takes it a few seconds to kick in so your oil pressure is up.

 

[bzingre]

No, It's right away

This morning, it didn't even idle, it started at 1000rpm. I know the bump up after a few minutes from 750 to 1000 is normal, but is starting at 1000rpm normal?

 

[lschultz]

Maybe the temperature was colder and it bypass the delay and went straight to fast idle. I'm sure some of them fellows that live where it gets colder than here will comment and give you there experiences.

 

[Dean Upson]

I started up mine this morning and it was 27 F. I was just wandering around the garage and the revs went up to 1000. I guess I'd heard that they go into fast idle, but it scarred the bejesus out of me, nearly dropped the coffee getting over to the truck to see what was wrong.



Dean

 

[Parshal]

Mine has fast-idled only once after 30 seconds or so when it was below 30 degrees. We've had lots of mornings and days of temperatures below freezing and my truck has never jumped directly to 1000 rpm. I'm wondering if mine is abnormal.

 

[JWerkheiser]

bzingre,



I had one occurrence where it immediately went to high idle on start. It only happened once. The rest of the times it waits a minute or so before ramping up. I thought it was unusual, too, and plan on keeping an eye on it.



James

 

[JWerkheiser]

Make that TWO occurrences. Happened today and it was 34 degrees outside. Motor was probably colder as it was 18 just a few hours earlier.

 

[DHess]

I don't think it's right that the idle goes to 1000 at startup. Mine kicked in once and did it after two minutes which is what I think it should be. Personally, I'd keep a close eye on it and if it does it any more I'd be checking with a couple of dealers.



Dave

 

[krabman]

Mine wont fast idle no matter how long it sits. The dealer is going to look at it next week.

 

[bzingre]

What is the default

I called cummins. They said that the ECM has to read certain parameters with certain values in order to step up the idle. I know about the parking brake or park and no brake pedal depression. Also, the inlet temp must be below 32F and the water has to be 190F or below. I don't know about oil pressure or anything else. Cummins said that I should take it back to the dealer as cummins shops can't work on this new engine, different diagnostic reader or something... Does anybody know the how this ECM is programed other than the above mentioned? In other words, is it supposed to jump to 1000rpm if it's below 20?, 18?

 

[Prairie Dog]

Just a note here, the local cummins shop said they will work on my truck but I have to go to the dealer if I want warranty to pay for it.

 

[bzingre]

Did it again

It did it again this morning. Went outside, let the inlet heater do it's thing, bumped the starter, engine starts instantly to 1000rpm. I am going to call the dealer to see if they can look at it. I can hear the bearing screaming at me... :-{}

 

[JWerkheiser]

Same here Brad. Mine did it this morning too.

 

[Dean Upson]

Mine did it twice so far. I told them at service about it and they are supposed to look into it.



Dean

 

[bzingre]

Talked to the Dealer

Talked to the cummins tech at the dodge dealer today. He is going to call cummins and find out what is going on with the instant high idle start. I asked him to let me know if this is normal and what options we have as far as flash file fix or a parameter change in the ECM. I will keep all you posted as to what I find. Nevertheless, I don't think it's right to have it instant high idle.

 

[Mr.Goat]

Well we have down and dirty winter here now. So I've been paying attention to this fast idle thing.



When I first start it up it idles at about 700. After 2 min. if you haven't touched the gas etc. it goes to 1000. It's been very consistant on this even when it was warm out. This is the way mines working anyways. Pete

 

[bzingre]

Found out from Dealer

Dealer called me back today. The technician talked to Cummins and they said that the instant start to 1000rpm is normal. There should be instant oil pressure to all bearings at start up. The purpose of the high idle is to reduce emissions and to quickly bring head temperature up. The high idle start is triggered by the water temp sensor and the inlet air sensor. The delay in any gage reading is due to a delay built into the DC side of the electronics. DC delays the gage readings to avoid displaying erratic gage movements on the gage cluster during start up. The engine pumps oil on crank. Anyway, if that's how they want it to run, I guess I will live with it. They said to avoid this, plug the truck in. I will be checking for flash updates in the future.

 

[Parshal]

Re: Found out from Dealer

Originally posted by bzingre

Dealer called me back today. The technician talked to Cummins and they said that the instant start to 1000rpm is normal. There should be instant oil pressure to all bearings at start up. The purpose of the high idle is to reduce emissions and to quickly bring head temperature up. The high idle start is triggered by the water temp sensor and the inlet air sensor. The delay in any gage reading is due to a delay built into the DC side of the electronics. DC delays the gage readings to avoid displaying erratic gage movements on the gage cluster during start up. The engine pumps oil on crank. Anyway, if that's how they want it to run, I guess I will live with it. They said to avoid this, plug the truck in. I will be checking for flash updates in the future.

Why is that mine has never done this? I've been starting it frequently in temperature below 30 degrees and mine has never done this. Does this mean mine is not working properly?

 

[Dean Upson]

Hmmmm... ... . Let me get this straight. It's normal for it to start at 750 rpm and go up to 1000 rpm a few minutes later and it's also normal to crank up to 1000 rpm right off the hop with the same ambient temperature perameters. Gottit!



Dean