6.7 08 Flat Spot

[RWolf]

I have about 2k miles on my 3500 dually with the manual and since the day I picked it up I have had a flat spot right out of idle. It does not matter if I am on it hard or soft when I shift it takes a while for the engine to come on, now this does not feel like turbo lag. This is my sixth Dodge with the Cummins. It took it to the dealer for him to check out and he said that all I could hope for was a software update and that at this time everything checked out. He had the mechanic drive around with me so he could feel what I was talking about, the mechanic said that he had already had several complaints about the same thing and all of them with the manual, he said that it was because of the way the new 6sd was made and also the torque release springs on the clutch disk. I have been around the block once or twice and I can hear a load of crap when it is thrown at me and that was what this was. Has anybody else had this problem?

 

[Bigwhitehd]

i have the same thing with my truck 08 g56. I also have a small little blurp when below 2k rpms that feels like the tps quit receiving voltage, it has yet to throw a code though.

 

[HBarlow]

I only have 800 miles on mine and it is a cab and chassis with detuned engine anyway so probably doesn't have the same performance characteristics as your dually pickup so I don't have an answer.



However, if I had to guess, I'd guess the new emission control crap reduces fueling at that engine speed range to prevent emissions.



If I looked in my right outside rear view mirror on my '06 when I put my foot in it just above idle I could always see black smoke with a completely stock engine.



I'd bet the new emission crap won't allow full fueling until boost is higher.

 

[RDHamill]

Could it have something to do with the dual mass clutch?

 

[jelag]

08 5500 with over 9K miles with the new auto... . NO problem...

 

[grasmo]

Today my truck began to randomly run like a scared ape. I wish it would run like run this consistently. It has to be this emissions junk. It feels like it has over 400 hp at the rear tire ... I know this because I have a dyno from my d-max..... Until today my truck has run like a pig, 200 hp. max if lucky. Also the exhaust brake will make the tires chirp slowing down in 3rd ,2nd & 1st. It is an automatic and I'm paddle shifting it down. It has never ,ever run like this. However it will only do it at random. The exhaust brake feels like it is compounding the resistance ... honestly it feels like I am appliyng the brakes.

 

[MCSloan]

I also have the hesitation or stumble. Has had it since i got the truck. They don't seem to have a cure for it however when the outside temp is below 50 or so it seems to bother less and sometimes is completly gone. The colder the temp the better it is. I am in Fl now for the winter and the stumble is back with the warmer temps. It makes it hard to make smooth shifts. The more agressive you are with the throtle the less you notice it. When driving normal is when it showes up the most. Have 12000 mi on truck now.

 

[JLDanner]

Today my truck began to randomly run like a scared ape. I wish it would run like run this consistently. It has to be this emissions junk. It feels like it has over 400 hp at the rear tire ... I know this because I have a dyno from my d-max..... Until today my truck has run like a pig, 200 hp. max if lucky. Also the exhaust brake will make the tires chirp slowing down in 3rd ,2nd & 1st. It is an automatic and I'm paddle shifting it down. It has never ,ever run like this. However it will only do it at random. The exhaust brake feels like it is compounding the resistance ... honestly it feels like I am appliyng the brakes.

I've had the same thing happen with mine - its always when its in regen mode - runs like a completely different truck, GOBS of power, can smoke the tires from 1 to 3rd gear - and the throttle response is ridiculously twitchy. Only lasts as long as the DPF temps are 1000-1200F you can also usually detect a slight "knocking" sound coming from the cummins. I wish it would run like that all the time... . dOo. *%^! Runs like a Katrina rat looting Walmart!

 

[FATCAT]

This may be due to the "drive-by-wire" of the new electronic throdle. There may be some hesitation when at first when the excellerator pedle is depressed. Not like the old throdle cable days.