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Discussion Starter · #1 ·
Somy truck has been having this "stumble" problem when shifting to o/d. I thought it was enginge related but now I'm thinking Turbo. Driving to work this morning I watched my Turbo gauge and noticed when the ole girl shifts to o/d the turbo dumps about 2lbs, stumbles, dumps one lb, stumbles, then dumps the rest. I was under very light throttle and was pushing 6-8lbs of boost. It is e99 so it has a WW already. Any ideas?
 

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What have you tried so far?
Check boots etc loose connections
Check for oil leaks in the valley
Fuel filter (is it clean)
Do you have enough air flow for your turbo?
pull off intake air hose to turbo spin the blades, check for not normal movement
, bent blades etc.
 

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Discussion Starter · #3 ·
Boots good. No leaks, fuel filter is good. How much play is too much play? If the fins are bent or broken can I repair it or do I need a new Turbo?
 

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Did you do a leak test on your CAC system?
Here's a diy

Also look for soot around the up pipe

Look shaft play, as long as the blade don't touch the sides your good.

As stated above, look for broken blade. You can't repair the wheel (will need a new one if broken) Yes the turbo can be rebuilt

What is your speed when boost drop? When cruising at 55 and the trans shift the O/D, the turbo pushing maybe 4psi and 10psi if i have 10k # behind

Sent from AutoGuide.com Free App
 

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Discussion Starter · #5 ·
No boost leaks. Speed is about 55 when it shifts and drops. I'll look at the turbo tonight.
 

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do you have a powerstroke capable scanner like AE? did you scan the truck for any code?

how old is your cps? and witch one is it?

anything to monitor ICP & IRP?

fuel pressure good?
 

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Discussion Starter · #7 ·
I've scanned all that so many times haha. Fuel pressure is good. Just put a new gray cps in. Had a blue one in. It did it with the blue cps too. No codes. Only code is an ebpv code and that's because I put a non ebpv pedestal in and the truck came stock with an ebpv.
 

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after the truck shift into O/D, boost drop and stumble, do you have power issue or if you press the skinny pedal the boost come back up?
 

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It always drops boosts between gears especially if your barely giving it fuel.

Try unplugging the redline to the wastegate. That will prevent it from opening via the pcm. It will still open mechanically

Turn OD off and rev it higher than it normally would then manually engage OD and see what it does
 

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Discussion Starter · #10 ·
No power issue at all. Just stumbles each time it shifts to o/d
 

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Discussion Starter · #11 ·
Blue99stroker. What if it still does it after I try doing it mechanically?
 

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It might be a transmission issue then.

Let's rule out boost leaks and stuff first
 

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