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Discussion Starter #1
My truck's major mods are a set of DPS stage 2 injectors and a 6 position DPS chip. The chip's power levels are high idle, stock, 50HP, 75HP, 120HP, and 160HP. When using the 120 and 160 settings at full throttle the truck cuts out. This even occurs w/ the 75 power level if I am in the throttle for an extend period of time (from a dead stop to about 70mph). Does this sound like the stock HPOP is not keeping up or is my fuel stystem not up for the task?
 

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When you say "cuts out" do you mean shuts off or falls off?
 

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Slow 6.0
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what year truck? single or split shot injectors? ever check ur ICP at wot?
 

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Discussion Starter #4
It does not shut off, it just acts like it is running out of fuel. On the higher settings it will pull real hard up to about 3200 rpm then it will surge for a second or so then it will shift.
 

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Discussion Starter #5
The truck is a 97 model. I believe the injectors are single shot and I am not familar w/ all of the accronyms. What does (check your ICP at wot) mean?
 

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injector control pressure at wide open throttle

the truck acting like its running out of fuel is a symptom of low ICP, the surge while shifting sounds like a tuning issue possibly not related to the ICP problem.
 

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Discussion Starter #7
In that case, no, I have never checked the ICP at wot. How do you check the ICP? At first I thought the tranny could not shift fast enough so the engine was over reving, but there are times it will rev to 3500-3800 rpm and be fine.
 

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I'd say your running out of icp. you either need a scannor or a 4000psi gauge to check your ICP. Is your check engine light comming on? I am running stage 2's in my 96 with a stock hpop and it runns strong at first then just kind of peeters out in the top end and sets the check engine light. I hooked a scanner to it the other day and in the high setting of my chip the icp never got over 1500 it should be around 3000. you also could be running out of fuel it would be a good Idea to hook a fuel pressure gauge up to it and check that.
 

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Discussion Starter #9
Yea that makes sense, sometimes after it happens the check engine light does come on. On the lower settings of the chip I can usually shift into 2nd and 3rd no prob then after I hit 4th it happens. On the highest setting it does it right as it shifts out of 1st. To make sure that I understand what was said. The ICP is just the oil pressure created by the HPOP to drive the injectors. So if that were the cause it would be time to upgrade the HPOP, right? Where would you connect into the system to monitor the ICP? Is there a port on the HPOP? When you said I needed to check the fuel pressure, I am not entirely clear on how the fuel is pressurized. Is the fuel brought to a higher pressure within the injector by a plunger mechanism which is driven by the HPOP? Which would mean I needed to check the pressure of hte fuel entering the bowl? If that were the case how would I splice in? Thanks for being patient!
 

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A loss of High Pressure Oil will just cause the CEL to come on and the truck just won't be as fast as it could be. Loss of oil does not casue a surge.
My bet would be the chip. Try another make of chip and see what happens.
If it still does it, then look toward fuel system.
I doubt your HPOP can keep up anyway, but it won't cause your surge. There's another issue somewhere...
 

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Is this a problem that has just came up or has this happened ever since installing the injectors and chip?

I agree with DZLJIM the HPOP not keeping up will make the power trail off but it won't make it run bad.

You do need to check the fuel pressure though. On the drivers side of the fuel bowl there is a fuel pressure regulator. It has a valve on it that looks like a valve stem on a tire. Remove it and hook a pressure gauge up to it. Run the gauge up to the windsheild so that you can watch it while driving. You should have 40 to 50 psi minimum at any throttle position.

If you haven't canged the fuel filter for a while then I would do that too.
 

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Discussion Starter #12
The problem has been there since the beginning. I love this web site, every time I get on I learn something new. Thanks for all yalls help!
 
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