"Dead Spot" at certain RPMs

[dmax_ty]

I have a problem in my tune that and I cannot figure out from the log as to what it may be.

The problem is at part-throttle acceleration, the truck will seem to fall on its face around 2100 rpms, pick back up, then fall off, etc etc.

Happens also with the cruise set, I can hear it fuel/defuel essentially and the truck more or less, lunges up the hill. Flat ground it doesn't seem to do it, so it leads me to think it's something in the commanded fuel delivery or in the desired and commanded boost tables.

Any help would be great, truck is an 07 LBZ.

 

[xtremebikr04]

I have a problem in my tune that and I cannot figure out from the log as to what it may be.

The problem is at part-throttle acceleration, the truck will seem to fall on its face around 2100 rpms, pick back up, then fall off, etc etc.

Happens also with the cruise set, I can hear it fuel/defuel essentially and the truck more or less, lunges up the hill. Flat ground it doesn't seem to do it, so it leads me to think it's something in the commanded fuel delivery or in the desired and commanded boost tables.

Any help would be great, truck is an 07 LBZ.

This a tune you made? If its a tune you made, post up a log or the tune and people here can help you figure it out.

 

[dmax_ty]

Here is the tune, I am working on the loading the log.

 

[dmax_ty]

Can't seem to get the log to load. It doesn't have any real glaring things that pop out that would lead me to the problem. Everything is nice and linear and looks good.

 

[gmduramax]

Did you log the maf sensor?

 

[whitetrash21]

Had the same prob in mine. EGR shut off in tune but no blocker plate. Had a dead spot in the pedal in all gears, smokey at low rpm and turbo surged when cruising in higher gears. As soon as I put the blocker plate in, the problem went away. According to Mike, egr was shut off, but it may have been stuck open.

 

[c20elephant]

Can't seem to get the log to load. It doesn't have any real glaring things that pop out that would lead me to the problem. Everything is nice and linear and looks good.

If your running windows XP, Vista, Windows 7 save it as a zip file.

Right click the file>
in the drop down click> Send to
in the second drop down click> Compressed (zipped) folder.

It will show up as folder with a zipper on it in the same folder...

 

[dmax_ty]

Had the same prob in mine. EGR shut off in tune but no blocker plate. Had a dead spot in the pedal in all gears, smokey at low rpm and turbo surged when cruising in higher gears. As soon as I put the blocker plate in, the problem went away. According to Mike, egr was shut off, but it may have been stuck open.

I'm thinking this is my problem. I have ruled out the maf, vane pos, and everything else I can think of. I will try having the EGR on just for shits and giggles.

 

[onebaddmaxxx]

Just unplug the EGR if its shut off in the tune. That will fix the issue :thumb:

 

[x MadMAX DIESEL]

Just unplug the EGR if its shut off in the tune. That will fix the issue :thumb:

Not if its stuck

 

[onebaddmaxxx]

If it was stuck it wouldn't just be laggy at 2100. My lly was the same way

 

[x MadMAX DIESEL]

So your saying telling the program not to function it is not the same result as unplugging it?

 

[onebaddmaxxx]

I have seen on my truck personally and a local Lmm, that just disabling it, and driving will cause these dead spots. The Lmm did not have a very aggressive turbo brake either. Once I unplugged it, it worked a lot better. My truck used to fluctuate boost real bad. Unplugged it and voila. Don't ask me ha

 

[dmax_ty]

Hmm that makes sense. I have a blocker plate that will be here tomorrow, plans are a complete EGR delete but not for a while.

I haven't driven the truck in a couple days so I'll have to report back after the blocker plate install.

 

[onebaddmaxxx]

Just make sure you unplug the egr valve

 

[dmax_ty]

I have it un-plugged now. Still gonna throw the blocker plate in there because they are known to blow open under boost.

Good thing I kinda tore it apart, found that a mouse (aptly named Gus-Gus) had decided to make the airbox a nice little food storage shed for the winter, 5+ cups of dog food crammed in that damn thing.

 

[onebaddmaxxx]

So since you unplugged the egr for it fix the problem