Exhaust Back Pressure

griz700rocket

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2013 6.7 that I'm having trouble with the throttle being jumpy right off idle. If I monitor throttle position it goes smoothly from 1-100. If I monitor boost it goes smoothly from 0-26ish. If I monitor exhaust back pressure it goes from 0-1-2 but then jumps to 6 or 7 and is then smooth on up. The issue occurs just before I see the EBP jump from 2-6. Also when you monitor boost vs back pressure they are very relative to each other aside from when its doing as described above.

Possible bad back pressure sensor? Truck did this stock but much worse now that it's tuned/d-leted.
 

griz700rocket

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Anyone point me to where this sensor is? I think it's the same as one from the dee-pf that I could swap to see if it makes a difference.
 

griz700rocket

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Update: Installed new back pressure sensor and it helped a lot. Still not as smooth as my 6.4 was but definitely livable.

Next question. If I lock the truck in 5th with my H&S turned to performance and hold it to the floor rail pressure stays at 24-25k till 3500rpm or so and then falls off quickly. Weak LPFP? Weak HPFP? Normal for a 11-14 HPFP?
 

sootie

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Update: Installed new back pressure sensor and it helped a lot. Still not as smooth as my 6.4 was but definitely livable.

Next question. If I lock the truck in 5th with my H&S turned to performance and hold it to the floor rail pressure stays at 24-25k till 3500rpm or so and then falls off quickly. Weak LPFP? Weak HPFP? Normal for a 11-14 HPFP?

I believe that is by design in the tuning. It takes tuning tweaks to get them to continue fueling above 3500 rpms.
 

griz700rocket

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Update: I'm still fighting this surge just above an idle. I still believe it's linked to the EBP somehow as it seems to jump at the same time the motor surges. I tried unplugging what I thought was the EBP sensor that I replaced earier in this thread but my mini-maxx is still reading EBP. It did throw two codes (P0373, P0471) with the sensor unplugged. Any ideas?
 

Black AOD

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factory CP4's aren't designed to fuel much above 3000 RPM in the first place. That's why Exergy made their improved CP4
 

T_W6.7

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weird, i have dual fuelers and custom tunes, but didn't experience anything like you describe prior to the tunes and fuelers either, I know some 2015 ish trucks are tuning nightmares
 

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