Truck dies with hard acceleration

[KBecker443]

Hey guys last month my fiancé and I had a gender reveal for our little girl we are having in August. We thought a burn out in my truck would be a cool idea for revealing the sex of the baby, I did a hand full of practice runs and on the 2nd and 3rd practice runs my truck would die when I got off the gas. I had to crack 3 injectors lines and reprime the fuel lines. Then it fires back up. It also happened when we did the burn out for the gender reveal and also happened when racing a Duramax, it took him quiet a while to catch back up but he also got to tow me home. Any ideas on why I would lose fuel pressure like that? I didn’t think with my upgrades I would out run the stock VP but I’m thinking that is my issue. Considering a HO Extreme VP from XDP. 

Edited April 1, 2019 by KBecker443

[Dieselfuture]

I was going to make a smart  joke about gender neutral bathroom, but since we're talking about your future kid I decided to hold myself back.

It does sound like you're running out of VP supplying fuel, if I get on my truck pretty hard it would almost want to die too. A lot of guys burp a throttle few times to keep it running after a race or whatever. You might have to learn to live with it or try a different  VP

I'd probably slow down on burnouts soon you'll need money for diapers.

Congrats

[IBMobile]

It never did it before with the same set up so what changed?

Do you have a draw straw fuel pickup?

What size fuel lines are run from the tank to the VP44?

What is the fuel pressure when you do a burn out?

Where can you do a burn out in Vegas with all the traffic and red lights?

[dave110]

. How does one do a burnout in a way that reveals a baby's gender?

[Tractorman]

12 hours ago, KBecker443 said:

happened when racing a Duramax, it took him quiet a while to catch back up but he also got to tow me home

 

Things like this shouldn't be talked about on this forum.  It's almost like using profanity.

 

- John

[KBecker443]

8 hours ago, IBMobile said:

It never did it before with the same set up so what changed?

Do you have a draw straw fuel pickup?

What size fuel lines are run from the tank to the VP44?

What is the fuel pressure when you do a burn out?

Where can you do a burn out in Vegas with all the traffic and red lights?

It’s happened since I installed turbo and quadzilla. 

Yes I have a draw straw with 3/4” lines from Fass to VP. 

The quadzilla fuel pressure gauge is so spiratic it’s 20 one second then 9 it’s not very consistent so hard to tell even on daily driving. 

Living in Henderson there’s a lot of small roads to screw around on. 

8 hours ago, dave110 said:

. How does one do a burnout in a way that reveals a baby's gender?

Do a burnout and run over a black bag with the baby’s gender color chalk in it. There’s probably 1000 videos online of it. 

 

7 hours ago, Tractorman said:

 

Things like this shouldn't be talked about on this forum.  It's almost like using profanity.

 

- John

I understand and am very sad to say that. But that is the severity of figuring this problem out. 

[kzimmer]

There are a few threads around in the last couple years that talk about your problems.

 

The fuel pressure reading being unstable is likely due to the location of your sensor. If it's too close to the VP, it will experience the water hammer effect, and get pulses that affect the measurement, and eventually destroy the sensor. I lost a couple cheap sensors that way. That was with a snubber, and sensor mounted direct to VP. Now I have the snubber and a needle valve barely open, and some extra hose.

 

With these trucks, if you go wide open throttle and back right off, especially on an auto, this can happen. Happened to me once, ended up towing it home to troubleshoot, ended up having to bleed the injector lines. After doing some research I came to the conclusion that because of high load and highly advanced timing, cylinder pressures were able to overcome the injectors after the pedal was lifted. After the VP pressure is lowered, some pressure still exists in the cylinder, enough to pop the injector and force some air into the fuel line.

 

I think in my case the injector pop pressures had fallen low as well, which wouldn't help the situation. I should note as well that my VP went about a year later (maybe sooner I can't remember the timeframe exactly)

[Mopar1973Man]

Auto's don't have an anti-stall feature. When you drop the throttle you have to do it slow towards the bottom. The idle software isn't capable of catching a rapid fall of RPM. 

 

If you getting high boost pressures while in the burnout it possible to push compression gases back up the injectors backward if the injectors are worn out and popping low as you drop the throttle suddenly. This would answer why the reprime and cracking the injectors. 

 

 

[Dieselfuture]

9 hours ago, kzimmer said:

After doing some research I came to the conclusion that because of high load and highly advanced timing, cylinder pressures were able to overcome the injectors after the pedal was lifted. After the VP pressure is lowered, some pressure still exists in the cylinder, enough to pop the injector and force some air into the fuel line.

So would a blow off valve help in this case, I've been thinking about getting one just to save the Turbo from barking

[kzimmer]

1 hour ago, Dieselfuture said:

So would a blow off valve help in this case, I've been thinking about getting one just to save the Turbo from barking

Good question, I'm not sure. I have also been thinking of getting one, or some kind of popoff at least to stop the barking. Maybe @Me78569 can program a throttle ramp down option into the quad... Hint hint... Haha.

[Me78569]

lol nope.   last thing anyone wants is a automated process to slowly ramp down fuel.  They call that runaway lolol.


I did actually mess with it, and if you try and do something like that the ecm gets pissed and kills power to everything.

[rogerash0]

My injectors aren't worn and I can kill mine from taking my foot out of a wide open pull. I have to ease out of the gas or else it kills the truck. That's because I have compounds though, making 55psi. 

 

Your probably running out of fuel pressure. I solved my fuel pressure problems a great deal by putting the airdog on a fuse block from Amazon for marine applications, instead of directly hooking it to the battery. And I tore the entire airdog harness apart and made sure every connection was 100%. My pressure still goes down to 8-9psi with a full gas tank and a 1/2" sump, and airdog 165 or 200, no difference. It's at 17-19psi at idle with a hydraulic gauge hooked up to monitor it full time. My quadzilla fuel gauge lasted maybe a year before crapping out. A manual gauge is easier to look at. Quadzilla doesn't give a good warning when it drops down low anyway, just that little yellow bar that you don't even notice when your actually driving.

[Evan]

Haha made you laugh 

[pepsi71ocean]

I'm running 1/2 line from tank to FASS then 3/8's from fass to VP. I'm also running a fass 150 spring cut down to hit 18psi at idle.

 

with the old 95gph spring i could go from 17psi at idle down into the 8psi range with my smarty on the right settings. I always would tap the throttle on the way back as I was slowing down. Burt with the 150 spring I may see 15 psi hammer on the floor.

 

The main issue is that cylinder pressure far exceeds the 4,300psi of your injectors, if your running hard like that with high boost pressure.

[dave110]

All this could be avoided by going back to the old fashioned way of handing out 'it's a girl' cigars