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Discussion Starter #1
So Im out at lunch today stop at a light and then when I pulled away very little boost. No noises, no codes, not in limp mode just 4psi of boost. What do you guys think? TCV? Im running IPD's HDTCV and I still have the original at home which was functional when I pulled it so I can swap that quickly when I get home and see what happens. I just thought I would check with you guys and see what else it might be. Buy the way I can hear the turbo spool up and the waste gate activating just not nearly as loud as normal. I just sent off the final payment today!!! YAAAAAAAAAA ITS MY BIRTHDAY YAAAAAAAAA!!!!!
 

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So Im out at lunch today stop at a light and then when I pulled away very little boost. No noises, no codes, not in limp mode just 4psi of boost. What do you guys think? TCV? Im running IPD's HDTCV and I still have the original at home which was functional when I pulled it so I can swap that quickly when I get home and see what happens. I just thought I would check with you guys and see what else it might be. Buy the way I can hear the turbo spool up and the waste gate activating just not nearly as loud as normal. I just sent off the final payment today!!! YAAAAAAAAAA ITS MY BIRTHDAY YAAAAAAAAA!!!!!
Happy Birthday
Could it be a boost leak? Check your hoses - that's all i got for now only coz it happened to me before :)
 

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Discussion Starter #3
I checked under the hood and couldnt find anything loose or detached. I have lost the coupling on the OTE pipe before and thats loud, I didnt hear any noises at all.
 

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If you pull the electrical connector on the TCV, you will run a max of your wastegate opening/cracking boost pressure. If the car boosts more than 4psi without the TCV plugged in (assuming your wastegate is properly calibrated to open at 6.5-7psi), then the issue probably lies with the TCV.
 

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Discussion Starter #5
Thanks George! If Im understanding what your saying, by unplugging the power to the TCV the turbo should boost again if the TCV is bad?
 

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Discussion Starter #7
Ill give it a shot and let you know what happens. Thanks again!
 

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+2

George beat me to it. The TCV unplugged, it'll boost based on mechanical limits and not electrical (computer/electrical actuators), the wastegate is mechanical and will only boost until that wastegate opens, pending on where its set it.

Also, if you have never adjusted your wastegate and your still boosting around 4.5 psi, don't be alarmed - adjustments vary over time as things loosen up, factory made a boo boo, etc. Just listen to what your engine is telling you. :)

Keep us posted and good luck.
 

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That's correct. Now that I think about it some more, if your TCV is stuck" in a certain postiion, disconnecting it may not have any impact on your 4psi boost limit. This would further isolate the issue to be TCV related.
The TCV will always FAIL open unless which allows boost to hit the wastegate unregulated. Disconnecting it will mean the valve is always open, and therefore you will only ever run wastegate pressure. This is a safety design. If it were to fail closed, the boost would run out of control. So yes, unplugging it is not going to prove anything.
 

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Discussion Starter #10
So the only way to tell if it's bad is to replace it?
 

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Discussion Starter #11
Don't know why I'm just noticing this but temp gauge is out too! Fuse maybe?
 

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Maybe swap with someone who has a known working one. You will need to allow it to adapt when swapping it too, because I am guessing your ECU has tried to compensate and failed...kind of like breaking in a new TCV.
 

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Discussion Starter #15
Ok since I have both of the issues together looks like a trip to the dealership for a software flash. Thanks guys for all the input. I'll get back to you on the verdict.
 

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You're welcome. Good luck!
 

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Discussion Starter #18
Ok, so same issue as TNN above. $130 later I'm out the door and they gave here a bath too!
 
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