Injectors miss with smarty

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zunkerduramax

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Jun 15, 2008
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I have a 2005 with 150% over exergys and everytime i load a tune into the ecm I have a horrible miss between 2000- 2400 rpms. It idles fine and above that rpm it runs just fine. I have tried different levels and adjusting the timing and nothing seems to work, its the newest tnt/r. Also retorqued the connecting tubes and injectors and everything is tight. When i return it to stock it runs perfect, any help would be greatly appreciated Thanks
 
What charger, lift pump, cp3 and tunes with adjustments are you running?
 
s475, fass260, dual cp3 (one stock one 120% over). It was running fine all summer pulling but then i drove it to a couple close pulls and it just started with this popping and missing. When it does it, the smoke is white. Seems to do it once it gets warmed up to operating temp. Ive tryed even and odd levels and timing between 2 and 3. it runs just fine when i remove the smarty from the ecm.
 
So it was running fine with the smarty and your set up before and then it started running bad. But runs fine on a stock tune now?
 
I put new batteries in it cleaned all the connections and grounds and it still has this miss/pop when I load the smarty in the ECM. When I return it to stock in runs just fine with no issues. But yes it was running fine with the smarty then I switched levels and now it has it's issue. I no major check engine light just soft codes for the grid heater delete and fan because of electric fans, it never gave me an issue before
 
What is the rail pressure and LP pressure when it starts popping? Tried plugging the PRV?
 
The rail pressure is around 20k and it doesn't fluctuate that much when it happens. Lift pump pressure is high like 40psi, could that be the issue? There is no prv in the rail the second pump feeds there.
 
zunkerduramax said:
The rail pressure is around 20k and it doesn't fluctuate that much when it happens. Lift pump pressure is high like 40psi, could that be the issue? There is no prv in the rail the second pump feeds there.
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No, 40psi is fine. Is that 20k at WOT? If so, that is low, not low enoughn to make it pop, but low.

Try running the Smarty on an even number with the timing all the way down, see if that changes anything.
 
No thats 20k at 2000-2400 rpm. So I should try running it on timing 4 because that is the lowest right?
 
The timing values have changed for some of the Smarty versions, making them all the same. #4 is the lowest timing setting on the new versions (and some of the old ones). Here is a link to the announcement: http://madselectronics.com/downloadfiles/New_5.9L_Tuning.pdf

On some twin CP3 setups running that high of a lift pump pressure can cause problems. Anything above about 20psi on mine (I normally run 15), and I get a lot of weird behaviors.

My suggestion first, would be to reduce the timing. Try #3 first, then #4. I would also reduce lift pump pressure, but try the timing first.

Paul
 
I stand corrected. Thanks for the update on the tuning info.
 
Well i have the lift pump pressure around 22-25psi. Loaded the smarty up on level 2 and tried timing on 3 it didnt do it as much but still popped a couple times in my 6 mile drive. Then i tried 4 and it was back to the same popping so Im out of ideas.
 
Maybe try timing on 2? If 3 was better than 4.
 
I also tried the timing on 1 with the smarty on level 2 and it still popped. I have a ssr just never messed with it enough to really feel a gain, I guess I need a dyno for that. I live in northern Wisconsin.
 
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