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Discussion Starter #1
Today, I noticed my car is only boosting to ~12psi. Obviously thats not right, it usually boosts to ~23-25. The only warning light on my dash is for tpms. As far as I can tell, nothing changed with the way it runs or drives, it just refuses to build the boost past 12.
Could this be a symptom of a crushed bov? And if so, how do I check it. I am going to pull the bumper and go over the intercooler/pipes and make sure there is no leak btw.

I did try to look, but a cursory search turned up no info.
Thanks in advance!
 

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I believe your thinking is correct with having a potential boost leak. I wouldn't push the car any more like that as it's really bad for your turbo to be letting it free-spin like that - shaft speed can get out of control with big boost leaks.
 

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Discussion Starter #4
Wouldn't a crushed BOV hold more boost?
Im not sure, I thought if maybe the diaphragm was crushed in a certain way, it could leak boost at all times.
 

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If it's fluttering is not holding or was crushed crooked/too much. Did you put it in the vice? Did you full or half crush it. If you went past flush with the vacuum line then you damaged the spring.
 

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I don't think you read the post correctly. It holds boost. Flutters when you let off slightly on the throttle. Operates normal when going full throttle or built enough boost to PFFFSSHHHH when you let off all the way. vs. light throttle.

So crush at your own risk. Wishing I had a stock one to replace it for now until I spring for a new one.

Crushed in a vice. I'm sure I went farther then I was supposed to. Probably 1/8" or greater crush.
 

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Discussion Starter #11
So, I checked for leaks all the way from the turbo to the throttle body (visual and pulling on the pipe inspection). Nothing, re-did the coupling on a suspect one, replaced a slightly cracked vacuum line from the wastegaste.
Car still will not boost up past ~12, once it does build to 12 I can hear either the wastegate or the BOV opening.
Anyone have any ideas?
 

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Sounds like you are running wastegate spring pressure. Check your solenoids. Do you have a 3-port or stock?
 

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I remember you had a thread where you asked if you should get tuned or not. Did you?
 

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Discussion Starter #14
I did not get tune. I am about to, but obviously I need to figure out this issue first. I did switch the lines on the solenoid (the ones coming from the intake and the wastegate) and boost was the same, although idle was rough, so I switched them right back.
How do I check to see if the solenoids are working correctly?
 

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Discussion Starter #15
Took off the wastegate solenoids and sprayed the connectors and contact patches with QD Electronic Cleaner, still no change. I have a 3-port, thinking of just installing it and being very careful with my right foot to see if I can get it to build past wastegate spring pressure.
 

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Do you have a tactrix cable? You didn't specify how you read boost, whether it was through the gauge or using evoscan/cobbap. You could just put your 3 port on and decrease your WGDC values by 35 percent. It would be much safer that way.
 

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Discussion Starter #18

I'm killing two birds with one stone. I contacted Chet and started my tuning process. Installed the 3-port and got a map that is supposed to make it work. I am fairly confident I installed it correctly, I even had a friend read the instructions and check over my install. put Chet's first map on the car, idled well, drove around town at part throttle well, decided to try and build boost, wouldn't build past 10.
WGDC is currently set to ~50% and should be building to 16ish psi.
Could my wastegate be borked?
 

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Take the line off the waste gate, apply 11psi to it and you should see the rod start to move. Either with regulated air or with a mivac pump thingy to test it.

unless its partially stuck open. Then that would be the suck. But can remove the pin and move the waste gate arm freely.
 

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Discussion Starter #20
Didn't have a easy way to put 11psi to the wastegate line tonight. Decided to up the WGDC in 5% increments, upped it from 50%-70%, only in the 79%+ throttle area. The result was 13psi. Which doesn't seem right.
Going to hook the wastegate up to my compressor in the morning, and go to Lowes and build a boost leak tester
 
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