07 "stumbles" occasionally while idling

[thorsbyrancher]

I have noticed in the past couple months when my truck is first started up, after idling for a minute or so, the truck "stumbles" or "misses" quickly then goes on like normal. I am running winter diesel, added fuel conditioner, and have changed the fuel filter. Any ideas? 105000 km on the OD.



Thanks,

 

[EDankievitch]

Look on here for a thread about adding some Outboard oil to your fuel to see if the problem goes away, seems that some FCA's seem to stick and will cause the stumble and the extra lube from the outboard oil will help, but the FCA will need to be replaced. Mine will stumble of Diesel and will buck when going down hill on cruse, when I run some Biodiesel it is better, I just ordered a new FAC...

 

[RPelletier]

My '07 has the done the same thing a couple times. I'd describe it almost like a hiccup. Idles just fine... hiccup... idles fine again.



Its only done it 2-3 times in 24,000 miles. I'm not wasting my time having a dealer look at it. I know all I'd get is a "can't duplicate".

 

[MA2LA]

My 06 has a similar issuse. run a good fuel conditioner through it and run it hard. Part of soe of the issues I have seen is that we aren't runing htese trucks hard enough to see egts that keep things clean.

 

[p-Bar]

EDankievitch is correct from past post this will troubleshoot the problem

 

[JCleary]

I have noticed in the past couple months when my truck is first started up, after idling for a minute or so, the truck "stumbles" or "misses" quickly then goes on like normal. I am running winter diesel, added fuel conditioner, and have changed the fuel filter. Any ideas? 105000 km on the OD.



Thanks,

Mine has done it since new, and I have 24k miles on it. I also have noticed a rougher idle lately. I'll try some 2-stroke oil, but maybe a new FCA would be a good idea?



My truck hazes with stock programming and gets horrible fuel economy, 13 highway if I'm lucky. Maybe these issues are related? I'm a little disappointed, as my ***-kicking '03 with the same size lift and identical tires would get 17-18 miles per gallon...

 

[HBarlow]

I think all the late model trucks do this when ambient temperature is very low and the grid heaters are cycling. The grid heaters draw a huge current draw which loads the alternator very heavy, probably instantaneously. Under normal operation the ECM control idle speed and compensates for air conditioner compressor kicking in or out or turning the steering wheel and loading the power steering hydraulic pump. My guess is the ECM can't always keep the idle perfectly smooth when the alternator is loaded real heavy to feed the grid heaters. My '06 did that and so does my '08.

 

[abrankod]

Indeed, the stumble happens on my 07 as well and it coincides with the grid heaters cycling.

-Dan

 

[KCurlee]

Guys, Ok , I am new to the Diesel World. I have a 07, 5. 9, Loaded. Now, What are all these acronyms you guys keep using? I have been reading the Register for a year now, The reports are right on the money... I Started using the laptop to look-up lift pumps (Just wondering). Please lets help the FNG (new guy)...

 

[HBarlow]

Guys, Ok , I am new to the Diesel World. I have a 07, 5. 9, Loaded. Now, What are all these acronyms you guys keep using? I have been reading the Register for a year now, The reports are right on the money... I Started using the laptop to look-up lift pumps (Just wondering). Please lets help the FNG (new guy)...

List the acronyms you are unfamiliar with and someone will define them.

I used ECM which means something like Engine Control Module. It's the computer that controls almost every function of the engine, fueling, turbo boost, etc. The PCM is something like Power Control Module but I believe it controls all the electrical subsystem, alternator, lighting, etc.

 

[TimothyLong]

Guys, Ok , I am new to the Diesel World. I have a 07, 5. 9, Loaded. Now, What are all these acronyms you guys keep using? I have been reading the Register for a year now, The reports are right on the money... I Started using the laptop to look-up lift pumps (Just wondering). Please lets help the FNG (new guy)...

Something that can really help you is a set of Dodge factory manuals for your truck. Not Chilton's or the like, but the ones published by Dodge. If you are new to the world of diesel and plan on doing your own work where you can, the factory manuals can really help you out. There are step by step procedures, diagrams, torque specs, special tools required, the whole 9 yards. They'll cost you about $100 or so and they are available in hard copy or CD-ROM, but they are worth their weight in gold. I am not a mechanic by trade, but I enjoy wrenching on my truck! I have a set for my '03 and they have helped me a ton! What I can't find in the factory manuals, I ask the folks out here on TDR, some of whom could write the factory manual. Anyway, you can get them on the web from Geno's or there should be a 1-800 number in the back of your owner's manual that you can call to order a set.

 

[JCleary]

I think all the late model trucks do this when ambient temperature is very low and the grid heaters are cycling. The grid heaters draw a huge current draw which loads the alternator very heavy, probably instantaneously. Under normal operation the ECM control idle speed and compensates for air conditioner compressor kicking in or out or turning the steering wheel and loading the power steering hydraulic pump. My guess is the ECM can't always keep the idle perfectly smooth when the alternator is loaded real heavy to feed the grid heaters. My '06 did that and so does my '08.

Mine stumbles in any temp, whether or not the grid heaters are cycling. It will sit there idling, then there's a pop, stumble, and perfectly fine idle again. It's almost like it's firing too soon when the intake valve is open, but I can't imagine that's happening with the super-retarded timing our trucks have...



IDK, not a big deal, but it's annoying...

 

[EDankievitch]

Just replaced the FCA what a diff nice and smooth and my over head display is reading correctly again not 5 mpg too high. Also the bucking while going down hill seems to be gone. Well worth the $100

 

[TimothyLong]

Come to think of it, my '03 has just started doing that this winter. Generally it will only stumble when the grid heater is on during the post-start heat cycle. I occasionally have a rougher than normal idle as well. By that I mean the engine sounds a tad rough and it vibrates the whole truck a little when idling, but under power it runs nice and smooth with no problems. Got 102K on it so I don't know if it's the lift pump trying to tell me something or the FCA like has been mentioned here.

 

[EZeis]

My 07 also bucks on cruise when going down slight hills. I also get a major miss every now and then. The strong dead miss has only happened maybe 4 times in 26K. The strong miss can be heard and the whole truck shakes, idle is fine before and after. Mine has happened without the grid heater. I may try a new FCA as well.



The dealer had no clue and said no codes were recorded. I told them its either the FCA or it needs injectors. Just got a blank stare.



Where you guys getting your FCA? Dodge, Cummins, or a fuel injection shop?



Thanks,

Earl

 

[RMaguire]

I've been getting a similar idle lately.



I also mentioned FCA and Injectors to the dealer and got the same stare. I wonder, is that a taught response?



Regardless, they ended up blaming it on the Water Pump they were replacing at 50k. A week later I've seen no improvement. I'll just live with it until I can replace the FCA myself or the injectors go out on me.

 

[JimB1]

I think the "stumble" is a brief electronic waste gate opening cycle.



The stumble is crisp, quick, and regular, soon after cold start.



Also the stumble is different from rough idle which I had for a tank or two which cleared up with some Power Service but I still get the stumble/electronic waste gate cycle, only with cold start up.

 

[TimothyLong]

I put some Stanadyne Performance Formula in my tank when I filled up last weekend. That seems to have helped mine.

 

[tinaanddale]

i am having also a miss when idleing its not consistent though but there is some smoke coming out of the tailpipe. just pulled code PO483

 

[tinaanddale]

its late guys sorry its on a 04 3500 4x4 advice would be very thankfull