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PLEASE HELP! Low BOOST! #

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#1
So I recently noticed my boost would not go above 17-18PSI. I was running a Deadhook Motorsports sage 3 protune for 93. I recently switched to a Dizzy E30 tune. Mods are as follows, CPE cold side, MBRP hotside, Injen Intake, Turbosmart 50/50 BOV, DEPO intercooler.

Im running stock turbo and stock wastegate.

I have loosened/inspected/retightened all couplers. Visually checked vacuum lines for splits or damage.

Boost will hit 17 and stay steady until regular drop off at high RPM. I have emailed my log to Dizzy and he said all was good and it must be something mechanical in the system preventing the boost from building to 24-26.

Does anybody have some advice please! I checked my wastegate preload and it looks to be in spec. is it possible the BOV is bad? or the wastegate actuator is bad? I don't really want to just throw parts at this thing if I don't need to. Please help!!!!!
 


OP
MrF1sTeR
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Thread Starter #4
Boost control soleniod all good? Bov could be stuck.
I will pull it today to see what’s up. Could the boost control solenoid effect it like that? I thought it self tests every time you run the car.
 


OP
MrF1sTeR
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Thread Starter #7
O-rings Flatten out over time under pressure and from heat
So I pulled the BOV and the main oring is very very flat. Like there is no difference in height between the metal and the oring. I’m sourcing one at some point tonight hopefully. But can that really create that big of a leak?
 


PunkST

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Menasha
#8
That would do it. Its right on the compressor side so its got no chance of building boost
 


Ford ST

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Pleasant Garden
#9
So I pulled the BOV and the main oring is very very flat. Like there is no difference in height between the metal and the oring. I’m sourcing one at some point tonight hopefully. But can that really create that big of a leak?
Question do you have the electronic 50/50? or a mechanical one?

Sent from my LG-LS997 using Tapatalk
 


OP
MrF1sTeR
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Thread Starter #10
It is the mechanical one. Is one worse than the other by chance?

Question do you have the electronic 50/50? or a mechanical one?

Sent from my LG-LS997 using Tapatalk
 


OP
MrF1sTeR
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Thread Starter #11
Update...replaced o rings on the BOV and boost still will not go above 17psi. I’m starting to think it may be the wastegate actuator. How easy should it be to move it by hand with the vehicle off?
 


OP
MrF1sTeR
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Thread Starter #13
I don't believe so I have the electric 50/50 version. Do you still have the sound symposer?

Sent from my LG-LS997 using Tapatalk
That is deleted as well! I’m so lost with this issue
 


PunkST

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#14
I dont think you should be able to move that by hand with the car off. Cound be wrong.
 


TyphoonFiST

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#15
If the actuator is off the vehicle hook a vacuum pumper up to it and see if it starts to move around the designed springs pressure to open.

Sent from my SM-N950U1 using Tapatalk
 


OP
MrF1sTeR
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Thread Starter #16
If the actuator is off the vehicle hook a vacuum pumper up to it and see if it starts to move around the designed springs pressure to open.

Sent from my SM-N950U1 using Tapatalk
Can I use this method with it on the vehicle?
 


OP
MrF1sTeR
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Thread Starter #18
Do you know the Springs Lb rating? is it stock? Turbo smart? Etc.....
It is stock, so I’m not sure of the spring rate. I have a turbosmart 7lb coming in the mail to replace the stock one.
 


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