LBZ: Top end

[Lbz_cody]

So I don't know if I just can't word this right or am just not wording this right in search but I noticed when I was running my truck my low end is really powerful and definitely puts you back in the seat but once I hit 4th gear plus it just doesn't pull near as hard and I'm wondering do you guys think this is a fuel problem like I need a upgraded cp3 or is that normal

 

[TeaBagger2006]

Fill out your signature so we can know what you have done. Do you have a way to see your command vs actual rail pressure?? Could be in the tuning as well or transmission is going out.

 

[TheBac]

What have you done to the truck? Assuming its an LBZ from your username....


EDIT: Treed by the Bagman.

 

[WVRigrat05]

Both my duramaxes loose some ass after 80, the LMM is closer to 100 in 5th but close enough.

 

[Lbz_cody]

So I have efi live
PowerShot 2000 propane injection which is old school I know I got the kit for free from my buddies totaled truck
S&b cold air intake is all I have

 

[WVRigrat05]

Who's tunes?

 

[Hot COCOAL]

I never noticed this problem with my truck...I did the FPRV shim, a shift kit, egr delete and the Hi flo CP3 kit when I did the tune...so maybe that's why?

I've always been impressed how this truck pulls thru every gear...the stock charger used to fall off pretty hard tho...I'd have to say it was around 100mph when I would feel it start to move out of its map...IIRC...that was a while ago

 

[WVRigrat05]

I can feel my fprv popping off it jerks like a dog humping air.

 

[Hot COCOAL]

I can feel my fprv popping off it jerks like a dog humping air.

?huh?
When it opens, it throws a code and goes into reduced power or limp mode, and the CEL has to be cleared IIRC...and the truck has to shut off IIRC, for the valve to reset?

Ah, and now that i remember, I did the shim about 2 weeks after the tune. Went to pass a car on a two lane HWY one night and lost power at their door, threw a CEL and P088 or something like that (low rail pressure)

I know when it happened to me I threw a code...that was that
Don't think it flutters, like a dog humping air?

When was the last time you guys changed your fuel filter? Ran an additive and cleaned the dirt out from behind your go pedal?

 

[1SloLMM]

Could it be he just needs a tranny build? Clutches change in 4th and if it's slipping it could cause the "dog humping" motion and not transferring power to the wheels

 

[Lbz_cody]

Who's tunes?

Kory willis

 

[WVRigrat05]

?huh?
When it opens, it throws a code and goes into reduced power or limp mode, and the CEL has to be cleared IIRC...and the truck has to shut off IIRC, for the valve to reset?

Ah, and now that i remember, I did the shim about 2 weeks after the tune. Went to pass a car on a two lane HWY one night and lost power at their door, threw a CEL and P088 or something like that (low rail pressure)

I know when it happened to me I threw a code...that was that
Don't think it flutters, like a dog humping air?

When was the last time you guys changed your fuel filter? Ran an additive and cleaned the dirt out from behind your go pedal?

I watched the rail pressure go from 27 and change to 22ish and back real fast every time I'm on my 150 or 230 tune and go wfo. Might be something else, but its done it since 11k miles.

 

[WVRigrat05]

Kory willis

Send him some logs.

 

[WVRigrat05]

Could it be he just needs a tranny build? Clutches change in 4th and if it's slipping it could cause the "dog humping" motion and not transferring power to the wheels

His looses power mine does slight jerking. Mine is built. Now that I think about my tired old raptor may not be keeping up being is the hours and miles on it.

 

[Lbz_cody]

I never noticed this problem with my truck...I did the FPRV shim, a shift kit, egr delete and the Hi flo CP3 kit when I did the tune...so maybe that's why?

I've always been impressed how this truck pulls thru every gear...the stock charger used to fall off pretty hard tho...I'd have to say it was around 100mph when I would feel it start to move out of its map...IIRC...that was a while ago

When you do a complete egr delete with the high flo Intake and everything and it says race tunes needed would my efi live be enough or do I need to get new tunes made

 

[S Phinney]

When you do a complete egr delete with the high flo Intake and everything and it says race tunes needed would my efi live be enough or do I need to get new tunes made

You would need new tunes for the deletes.

Sent from my SM-G920V using Tapatalk

 

[Lbz_cody]

Thank you

 

[bluessmax]

Thank you

1. If its dumping rail, its like FPRV popping open. With a log I can help you confirm this.

2. No updated tunes should be needed for EGR delete- I already have it killed off in the base files.

3. If you are running more than 150hp - You will need a lift pump.

4. Send me a log and I can answer your questions in a hurry and save you some time.