EverydayDiesel
I drink diesel
- Joined
- Feb 12, 2016
- Messages
- 196
Hello,
You guys are a lot smarter than I am so I need help tracking down a surging/bucking problem that I am having on this 2007 6.7 cr when the transmission(68rfe) locks up 5th (or 6th) gear from 1000-1200 rpm only.
Some background on this build
new QSB wide bowl pistons
new hamilton cam/pushrods/springs
new exceedy 350%
new firepunk compounds
new ats dual fuelers
new duramax top cp3 with new cummins fca
new fish tuning dual cp3 controller (i have a new ats controller also but search say they are problematic)
efi live tuning by les
new carillio rods
new 230 aeromotive lift pump
new fleece fuel bowl delete/dist block (new baldwin 15 micron w/f separtor and new cat 2 micron fuel filter)
Lift pump pressure holds steady at 9psi (mechanical) - i can turn this up or down
cummins cp3 (oem cummins fca) was working great before this build
on an early tune the truck would buck hard (harder then the brakes could hold) any time in drive or reverse but les has tuned that out. Now it only happens at low rpm (1k-1200) and gets progressively worse with more throttle. (a lot of black smoke when it bucks that comes out in pulses from the exhaust the same rhythm as the surging)
I am pretty good with a fluke volt meter. What would cause this bucking/surging at low rpm only? Any help is greatly appreciated!
You guys are a lot smarter than I am so I need help tracking down a surging/bucking problem that I am having on this 2007 6.7 cr when the transmission(68rfe) locks up 5th (or 6th) gear from 1000-1200 rpm only.
Some background on this build
new QSB wide bowl pistons
new hamilton cam/pushrods/springs
new exceedy 350%
new firepunk compounds
new ats dual fuelers
new duramax top cp3 with new cummins fca
new fish tuning dual cp3 controller (i have a new ats controller also but search say they are problematic)
efi live tuning by les
new carillio rods
new 230 aeromotive lift pump
new fleece fuel bowl delete/dist block (new baldwin 15 micron w/f separtor and new cat 2 micron fuel filter)
Lift pump pressure holds steady at 9psi (mechanical) - i can turn this up or down
cummins cp3 (oem cummins fca) was working great before this build
on an early tune the truck would buck hard (harder then the brakes could hold) any time in drive or reverse but les has tuned that out. Now it only happens at low rpm (1k-1200) and gets progressively worse with more throttle. (a lot of black smoke when it bucks that comes out in pulses from the exhaust the same rhythm as the surging)
I am pretty good with a fluke volt meter. What would cause this bucking/surging at low rpm only? Any help is greatly appreciated!