Got some quick questions about my new '06

[JGheen]

So I just bought my new '06 3500 4x4 Mega Cab and had a few questions about starting it and some starting things that have happened since my 2 days of owning it.

I am wondering why there is no "Wait to Start" light on the dash when I turn the key to the On position? The owners manual says it should come on every time. Do the trucks bought in California not have grid heaters or any type of fuel or air pre-heating starting aids?

Also on starting, the "Check Engine" light comes on in the "On" position (while I am waiting for the "Wait to Start" light which never appears) and stays on until I start the engine. The owners manual says it is part of the ECU's emission's test cycle during start up?? Can someone tell me more... . ?

Another thing I noticed is, the idle will flux around after I take it out of gear. For instance, I can be cruising down the freeway and coming to a stop at an exit and after down shifting from 5th to 4th or 3rd and as I am coming to a complete stop, the idle will bounce slowly from around 500-600rpms to 800-900rpms. Is this something typical you guys have seen on yours??

Sorry if these are obvious questions to you familiar '06 owners, I'm a long time 12v, mechanically fuel injected mind and am very new to the common rail fueled beasts just trying to adapt to electronically controlled fueling and timing. Paid a bunch of money on this rig like the rest of you and want to know what, if any of you had similar issues like I may be having. Other than these weird instances with the new rig, I am absolutely grinin' from ear to ear at every turn of the key.



Thanks, Joe

 

[TAbbott]

Congrats on the new truck. I think you'll be glad you got the '06. I've seen several threads regardig the wait to start light not coming on. Lots of folks say theirs won't come on until the ambient temperature drops a bit, like down to 60 degrees or so. Doesn't seem to be an issue as far as starting is concerned. Mine comes on every time, just as you say the book says it should.



I'd be more concerned about the hunting for a steady idle speed. If you have delayed a bit in depressing the clutch (let engine rpm drop below idle speed while clutch is engaged and transmission in gear) and the ecm is trying to add fuel as you then depress the clutch, that may cause the symptom you described as the ecm will add fuel trying to maintain at least the set idle speed and then it overuns a bit when the load is removed. My idle is really rock steady once the engine warms up. Prior to reaching operating temperature, like when its first started, the idle speed is a bit higher but will slowly ramp down as the temps come up. Not the fluctuations you describe, which in a mechanical engine I'd be tempted to attribute to it sucking air somewhere.



About the grinning, it'll probably take a while for that to wear off. The grin'd probably go away lots quicker if you'd ended up with the 4. 10's!

 

[wcjp]

The "Wait to Start" is now a little coil that appears on the left side of the dash. Only wait to start in cooler temps. Your sig indicates you're in California. Sounds Normal. The idle thing I know nothing about.



Did your truck come with the 7micron fuel filter? New TSB out about one month ago says to convert from 10micron to 7micron fuel filter. TSB also says to dump water in fuel drain valve monthly.

 

[Prairie Dog]

My 03 has done the idle drift thing since new, I wouldn't worry about it.

 

[BDeMartile]

The idle flucuation you speak of is normal under the conditions you stated. If it hunts at idle after it is stopped then there could be a problem. You should see the coil (amber in color) glow for less than a sec then go off if the ambient is ablove 60. If the engine is above 140 then you wont see the light.

 

[olznut]

I RARELY see the wait light, and I'm just down the road from ya (I work at the Castaic truck scales). The only time I saw it was during the little cold spell earlier this year, when it was in the 40's and below I would see it. Saw it when I went to Yosemite, but it was chilly as well.

 

[JasonCzerak]

yeah, the bouncing idle when slowing down is normal.



you will also notice that if you're in stop and go traffic where you are on a decline and just let you foot off the break and allow gravity to move you that the RPMS will increase 200rpm or so. For what reason? I would love to know.



possibly could be something in the ABS system that wants more rpm to allow for better breaking?

 

[rashwor]

I have a '05 with 74,000+ miles and my grid heater works as you indicate your does. It will come on and work as it should when the outside temp is around 40*F or below. Also, I have had the idle hunting exactly as you describe since I drove it off the dealer's lot with 8 miles on it.



All sounds normal to me. Happy motoring! Oo.

 

[JGheen]

Thanks for the replys guys, I am feeling much better about those small observations I was concerned about. I definately understand the idle hunting now, sounds like it is typical with the 6-speed trucks.

Good to know about the "Wait to Start. " Sure would be nice if the owners manual for your brand new, $40K truck would have the proper, updated instructions inside with accurate illustrations.



Does anyone have any similar occurances with the "Check Engine" light not going off until the engine is started?? The trusty owners manual says it is an emissions thing, so is it just running it's diagnostics and staying on then flashing until the truck is started and it detects exhaust gases?



Another occurance that has recently been happening ever since I got the truck off the lot :{ , is some hard starting and about 5-6 seconds of solid starter cranking before ignition finally starts. Seems to only happen when the truck sits overnight and periods longer than 4 hours.

If I stop somewhere, shut it down and then in 15-20 minutes later I start it up again, it fires right up with no more than 1-2 seconds of cranking. But the morning I drove it home from upstate this past weekend it took about 5 good seconds to fire up, this first morning of taking it to work it started hard again. Even after work to go home it took some cranking, so how normal(which I find hard to believe would be normal) is this?? It's like it is loosing fuel prime but not sure.....



Thanks for the help guys, Joe

 

[TAbbott]

Sometimes my '06 has the long crank issue as well. As near as I can tell from reading lots of posts on here is that it normally is an issue of 2 engine sensors on different parts of the engine needing to agree exactly on the engine timing. Each has to say simultaneously "we're at Top Dead Center" and until they do that, the ecm isn't gonna release any fuel and its not gonna fire. Supposedly there's enough lash in the gear set up or flex in the crank or something that sometimes it takes a bit for them to agree like they're supposed to. Anyway, my long cranking spells have been coming fewer and farther between as time goes by. I now have about 6500 miles on my truck.

 

[AKaiser]

I thought only old 6V71 and 6V92 Detroits loped like that at idle. Never heard Cummins or IHCs do that. A Cat or Mack motor, maybe. Interesting. Of course, Detroit 6V motors ALWAYS lope at idle. :-laf

 

[rashwor]

Long starts are sporatic with my '05 and have been since new. All the sensors have to agree life is good before it is allowed to fire. Sometimes mine maybe upwards of 5 seconds.



The old 12 valves spoiled us (Cummins owners anyway! :-laf ) all to firing the first time they turned over!

 

[AKaiser]

The old 12 valves spoiled us (Cummins owners anyway! :-laf ) all to firing the first time they turned over!

IH DT466s are the same way (the ones we have in our farm equipment). I remember barely touching the key in 20 below zero conditions and that tractor would start right up. I think alot of it was the high compression and good Bosch pumps.

 

[SOsterday]

I'm new to diesels and my new 06 is my first. But from my gas auto experience I know that when the A/C compressor cycles it will increase the idle RPM. Perhaps it's doing the same thing here and causing your symptoms. In case that is it, it's perfectly normal.

 

[mlewis73]

I have noticed that if my engine is hot, sometimes it won't fire off immediately. Same problem in the mornings sometimes.



I have made it a habit to STOP cranking if the truck doesn't start within 2 seconds. I'll crank it a second time and it fires right off.

 

[JGheen]

Thats what I thought about the long cranking. Thanks for the confirmation on that, guess I will just have to get used to it and hopefully mine will get better as the miles go on.

What about the "Check Engine" light that stays on until the engine is fired up?? Anyone's do this as well?



Thanks again, Joe

 

[TSpecht]

For the idle hunting while vehicle is in motion, try the following. If you have plenty of distance between you and the vehicle in front of you, shift out of gear, release the clutch and wait about 2 seconds before hitting the brake (basically wait until RPM stabilizes). Idle speed seems to stabilize at ~900RPM when doing that method, and once you hit the brakes after that, it seems to find the 750RPM normal idle setpoint. I suspect it's something to do with the engine not seeing the load it's expecting to see at that speed, and the programming isn't perfect for that particular situation. Shouldn't harm anything though from what I can tell...

At least the above seems to apply to my 2005 in a repeatable fashion...

 

[BDeMartile]

I could be wrong but I thought I read a post that talked about a dealer reflash to cure the long start???

 

[JohnJoyce]

I also have the starting problem with my 06 truck after a month of ownership. Never had it with my 97 12v. The regrets are building up.

 

[JasonCzerak]

heh, just wait until you start hearing things



these motors are so quite you start hearing all the little things and you wonder if somethings just going to fall off.