please help.

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Pyccak

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Guys please help me. Here is what's going on. I have 2002 f250 with 95 12v cummins which came out off of 95 dodge auto truck, i installed p-pump off of 1996 12v 5spd truck, then i did 4k gsk and 60lb valve springs. I also grinned my fuel plate to #100, and did full tune up on AFC. The truck was running grate and i was pushing about 32 psi of boost with stock injectors (165 hp out of 95 auto truck) and turbo, then i upgrade my injectors to stage 2 75 hp ddp and i clogged my wastegate. Now about my problem, as soon as i installed injectors i did got more power, but my boost went down to 21 psi and i have a lot of smoke in low rpms and very low power but as soon as rpms go up truck just jumps and goes. Another problem is very bad start. In warm days its starts but takes lots of cranking unless I press a gas pedal, then it starts right up. In cold days like 55* (I never tried to start it in weather colder then 55 F, because I installed injectors in March. Maybe it won't start at all if it's going to be below 55F. I don't know yet) it will not start if i don't give it gas and i have to keep my foot on the pedal for like 5-10 seconds before i let it off or it will die. My question is what can i do to raise my boost to at least 32 psi and make turbo to spool sooner and faster because i feel like truck needs more boost and faster,as soon as rpms go up i get like 10psi smoke clears, how do i clear smoke sooner?? And how do I get my truck to start better? Forgot to mention i have 3.5" exhaust turbo back for like 1 feet then it goes to 4" and in the middle of the truck its changing to 5" and out to a tip 6".
 
Did you adjust the governor arm to that plate? sounds almost like its hanging up on the edge of the plate somehow. Or the AFC is keeping the fuel down up to a point, then allows a lot of fuel suddenly. You can test the AFC with shop air, make sure it is moving when it should.
If you adjust idle to 800rpm with the AC on, in drive.. do you still have starting issues? Might want to look at the gov springs.. a click or two. Whats your timing at? High timing makes it harder to start. I usually run low timing in the winter.
Might be an air leak in the fuel line too, hard to say. I run a boiler sight glass in the line before the pump so I can see the air.
 
Yes it is adjusted, IN AFC I have smaller washer and I tried to adjust with air but it was opening all the way at any psi I tried, so I left spring in the middle. Timing I have 16* but it was running and started good before I got injectors. I know for sure no leaks in fuel or air. Why do u think I Lost boost?? More fuel = more boost, I got more fuel but I lost boost.
 
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Try these (not in any specific order):

-tighten the starwheel
-try #8 or #6 plate
-check AFC housing location (not always best in FF)
-check fuelplate location (not always best in FF)

You need to tune less fuel in low rpms, that's the ticket. 35psi is recommended max but with good setup the stock turbo will go beyond 40 easy. But that is not a good thing as its going to be hot air and EGT will go through the roof.

Bigger sticks often require slight pedal to start. It will start at any weather if the batteries are full and the fuel is suited (or mixed) for cold weather.
 
JariV said:
Try these (not in any specific order):

-tighten the starwheel
-try #8 or #6 plate
-check AFC housing location (not always best in FF)
-check fuelplate location (not always best in FF)

You need to tune less fuel in low rpms, that's the ticket. 35psi is recommended max but with good setup the stock turbo will go beyond 40 easy. But that is not a good thing as its going to be hot air and EGT will go through the roof.

Bigger sticks often require slight pedal to start. It will start at any weather if the batteries are full and the fuel is suited (or mixed) for cold weather.
Click to expand...


tighten the starwheel all the way???? i have new batteries it turns good and fast its just' don't start till i press gas pedal.
 
your gov springs are probably one click too tight if its not starting easy.
 
You want to tune your afc, first you gotta get the preboost fueling where you want it (smoke screw) then tune the starwheel so that the fuel comes on with the boost appropriately. Enough fuel to light the turbo quick but not so much it just bogs and pours out black smoke. AFC housing position always plays a part, moving it forward increases fuel.
 
alex211 said:
You want to tune your afc, first you gotta get the preboost fueling where you want it (smoke screw) then tune the starwheel so that the fuel comes on with the boost appropriately. Enough fuel to light the turbo quick but not so much it just bogs and pours out black smoke. AFC housing position always plays a part, moving it forward increases fuel.
Click to expand...

i have not touch smoke screw it is in stock position, i have way to much smoke that i want to clear. i will try to move my AFC back and tight my star-wheel and see what happens.
 
That should be a good start, you may also want to move the fuel plate back some as well.
 
ok some updates, i removed my fuel plate and tighten my star-wheel and yeah the truck just goes from the start like never before and lite smoke, i love the way its acting right now but i still feel that it needs more boost, now its getting about 22-23. My question is can i leave my truck without fuel plate or do i need to put it back?? its run very good i don't want to mass up again.
 
I'm not running a plate and I have the stock sticks and turbo, I can hit 40 psi of boost with no problem.
 
Are you still getting a boost signal into the AFC? If you plugged the wastegate you may have disconnected the line from the intake side to the pump? Does it take RPM to make boost? Or does it jump to 22-23.
 
I do have new line made from intake to AFC, so its all working. To get 22 psi i need to accelerate very hard and it takes some good rpms to get boost, i feel like my truck will explode of high rpms, but i dont know how many rpms i have because i never got rpm gauge working with 12v cummins i need to buy adapter. So its very hard to get some boost, like i said before i use to run 32 psi it was nice i can hear engine was doing good without trying to explode.
 
alex211 said:
I'm not running a plate and I have the stock sticks and turbo, I can hit 40 psi of boost with no problem.
Click to expand...

what exhaust you have?? my brother use to have dodge with stock turbo and 4" exhaust turbo back and #11 fuel plate and boy he was running 38 psi like piece of cake, his truck was jumping like a deer from start and he was getting 22 mpg on the hwy.
 
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What exactly did you do to the waste gate? I remember another guy having a similar problem building boost. He thought he had wired the waste gate full closed but it was full open instead.
 
i closed it before i put turbo back, so i know for 100% that it is closed. if AFC was leaking i would not heave any power but my truck runs very good i just don't have enough boost for it to go easy.
 
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