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Discussion Starter #1
my truck is hanging the 4-5 shifts. I go WOT 1st-4th shifts beautifully then it hangs the shift to 5th. i gotta let out (quite a bit) then it will catch 5th and take off again. Is this something a TCM tune will fix? or do i have a different problem....
 

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Discussion Starter #2
i also noticed a CEL came on when it hung up. but im about 98% sure its a p0802 that ive been dealing with for a few weeks. is that related to the hangin shift? bump
 

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Im Superrrrr!
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Check your fueling....betting you are draining the rail at shift.
 

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Discussion Starter #4
that what it feels like i just didnt think my cp3 would be letting pressure fall. why would it do it to just the shift? cause after it catches 5th, it seems to run perfect. am i looking at needing to get a better pump or would a lbz reg fix it?
 

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the reg might fix it.....just log it and see where that gets you.

I was having a huge issue with that when I went to PA to race.

Soon as it did its final shift...hanging shift and CEL immediately. I was dropping prob 5-6k rail pressure instantly.

Granted I was spraying fuel out of the rail pressure sensor.
 

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Discussion Starter #6
maybe its a fuel limp code idk. it didnt limit rpms at all. did the lbz reg fix yours? if not then i guess i gotta start saving for some dual fuelers
 

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mine would never limit rpms...it did that with the lbz reg...

It only adds about 10% to total available fuel IMO

Its a cheap upgrade, but the overall net you gain is kinda low.
 

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Discussion Starter #8
ya. and it wont cure a dying cp3. im gonna throw a new fuel filter on it and see if that helps. if it doesnt and logging conforms im losing rail psi, then dual fuelers it is
 

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Discussion Starter #10
i know it will help. i was just wondering if the reason im hanging that shift is because i need a tcm tune with this charger. i guess we'll see after the logs
 
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