Here is what is happening for my truck. Any power level above ZERO and any tune including DEFAULT tune will do this. ZERO level is clean and smooth no issues. Reflashed my Quadzilla with the current tune and even dumped my iQuad App and reinstalled.

 

 

Edited August 1, 20177 yr by Mopar1973Man

try increasing fuel load timing by 1.5* 

? I will try that out tomorrow! I will definitely get to work on time lol thanks

@Me78569 I assume you mean what's labeled max load timing offset?  In the extreme tune it is already 2.5º of a maximum 3º

Extreme.json

If that doesn't help then drop your rpm timing at that point by 1*

put that to 3* and drop the rpm value in the area of issues by 1*

Well I did that with little to no change..I'm down to timing safe enough for a truck with a dollar tree head gasket and used head bolts

what rpms and what % of fueling does this miss / buck happen at?

 

Also only on wiretap levels?  

Seems to be 2200-2700 ish rpm not under full throttle fueling would be 75-100% depending on tune and seems like only on wire tap levels yes

Try setting fuel stretch down to 1600   with your injectors 2000 is a ton of stretch.  The pump may be running out of fuel

DUH!  LOL I guess I didn't even think of that! I will try that tonight! I'm guessing that it's the ticket. Especially since it even died 2 times after hard pulls now! Thanks 

I've spent to many hours working on this damn truck! 

So I have gradually pulled the wire tap clear down to 1300 and there's no change. It's almost as if my wiretap is turning on and off for some reason. It should come on at 10 psi minimum 25% I would think that I could feel it hit but I cannot. I am going to look over the wiring and make sure that tap has not come loose or something because that's kind of what it feels like. 

Can you export the tune you are using?  The exterme tune doesn't match the 25% number.

Here ya go

iQuad-Extreme-2017-11-21-09.10.032054464996.json

Does the buck happen under 10 psi of boost?  

 

Does it help to drop min wiretap % down to 0?  Currently the tune is setup to make wiretap go to %25 if you are hard on the throttle once boost hits 10 psi.  I would wager that you would get a good buck at heavy throttle when you pass that 10 psi mark.

 

Are you %100 sure it only happens on wiretap levels?    

7 minutes ago, Me78569 said:

Does the buck happen under 10 psi of boost?  

 

Does it help to drop min wiretap % down to 0?  Currently the tune is setup to make wiretap go to %25 if you are hard on the throttle once boost hits 10 psi.  I would wager that you would get a good buck at heavy throttle when you pass that 10 psi mark.

 

Are you %100 sure it only happens on wiretap levels?    

I will double check the other levels in the morning but I haven't got it to do it on canbus or stock levels...and it is bucking from 22-2700rpm when doing HARD but NOT WOT acceleration. I think I noticed it slightly on wot pull once tonight but not sure... It's almost like chugging.. And I have more than 10psi at the time it happens but I have been meaning to lower that and lower the minimum pump tap% as well for this tune. 

 

Also has done it on multiple tunes with multiple tap, timing, and fueling settings...I have only noticed it on wire tap levels

So I'm beginning to think that this is possibly an injection issue. Today I noticed while cruising at high RPM, I went in for at nearly 70 mile per hour just cruising and there was kind of a Lope if you will. I turned it down to the stock setting and it still did it just not as bad. I think that the can bus and wire tap fueling are just amplifying it. I was really thinking that I might have got my issues figured out but it kind of seems like I still have injector problems. Actually right now I'm cruising 45 at just over 1500 RPM and under light load it's loping at this RPM to

Noticed this forum awhile ago and have the exact same problem with the shudder and then started noticing it cut out at highway speeds, worse pulling a trailer. I watched by quadzilla data display and noticed the boost randomly dropping to zero when the shudder occurers.  I did replace boost sensor with oem Cummins part, going to hook up scanner to obdii port and see if the Cummins ECM is registering boost drop out as well.

 

Thought it may help to throw my two cents in as well

 

 

 

Edited March 19, 20187 yr by Trombly