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when im boosting especially in first gear, right when im reaching peak boost, the car jerks me around like three times hard then goes again. is this a turbo issue or a wastegate issue. sometimes i hear a weird hissing sound over the turbo spool noise. i am not reaching fuel cut im runnin like 8-9 lbs max.
 

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Just some newb.
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It actually sounds more like a bad boost leak issues. I would do a visual check on all your piping and look for rips or tears in the rubber hoses.
A good way to really check is to pressurize the compressor housing of the turbo and cap the 3000 pipe by the throttle body and use a leak down tester and some soap and water.
 

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you have a boost leak. you wont ever hit max pressure with aboost leak but youll still smack fuel cut early on. you can build a nice pressure tester with a couple small things from home depot, a ball valve/pressure regulator screwed into a pvc cap that is tightened onto a rubber coupler for plumbing....been using mine for a while now, works awesome for finding leaks, and you can test your system for the pressure your car runs.
 

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What about when it never stops building boost? I'm hitting 20+psi and fuel cut in 2nd. It takes forever to spool but it jumps hard when it does. 2nd 3rd and 4th I have to back off slightly otherwise it just keeps building. 1st isn't so bad, I'm only hitting about 12-14 in 1st with no problems. anyone running a ProfecB? I'm thinking it has something to do with that.
 

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Just some newb.
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What about when it never stops building boost? I'm hitting 20+psi and fuel cut in 2nd. It takes forever to spool but it jumps hard when it does. 2nd 3rd and 4th I have to back off slightly otherwise it just keeps building. 1st isn't so bad, I'm only hitting about 12-14 in 1st with no problems. anyone running a ProfecB? I'm thinking it has something to do with that.
If you are on stock fuel I would check your vacuum lines to your wastegate and make sure something isn't goofed. Boost creep can be a real killer.
 

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If you are on stock fuel I would check your vacuum lines to your wastegate and make sure something isn't goofed. Boost creep can be a real killer.
stock fuel as in pump gas?? That's all it has seen so far is 93. As far as fuel system goes : RC 550's, Walbro, AFPR, new Fuel Filter.
The lines to the wastegate were installed in accordance with the ProfecB manual. I will definitely check them over again. It wouldn't hold boost at first, now it's over boosting since i got the exhaust opened up. The weather is a lil bit on the fritz today so i will more than likely have to check tomorrow or Saturday. I plan on checking everything over to the best I can. Just wondering if anyone had anything similar happen with their setup. I'm going in to Boost Logic on Tuesday to have it tuned. It's running really funky, but that will change soon.
 

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What about when it never stops building boost? I'm hitting 20+psi and fuel cut in 2nd. It takes forever to spool but it jumps hard when it does. 2nd 3rd and 4th I have to back off slightly otherwise it just keeps building. 1st isn't so bad, I'm only hitting about 12-14 in 1st with no problems. anyone running a ProfecB? I'm thinking it has something to do with that.

My friend has the some problem,. but he is running aem ture boost., It will hitting around 10psi+ pleases assist how you fix yours... ~
 

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all vacuum lines dealing with the EBc are brand new as of now. it's still not registering anything. I took lines apart and blew into them with it attached to EBC and it takes a lotta air to register anything. AFPR acts the same with vacuum line plugged or unplugged. absolutely no change in FP. The filter for the ProfecB looks brand new and has little resistance when blowing through it. All lines are in tact and are brand new dealing with the EBC. I'm throwing the code 34: Turbocharger pressure signal. but it's funny because both the stock gauge and the one I put in are registering both boost and vacuum. Both are functioning what appears to be normal.

I'm stumped. i checked the resistor solenoid and it checks out at 3 ohms like TSRM says. Haven't found how to check pressure assy located right next to it. Hoping it's something simple but I'm lost as of now.:stickpoke
 

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def a boost leak, then fuel cut.
 

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ƒ=1/2π(√k/m)
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when im boosting especially in first gear, right when im reaching peak boost, the car jerks me around like three times hard then goes again. is this a turbo issue or a wastegate issue. sometimes i hear a weird hissing sound over the turbo spool noise. i am not reaching fuel cut im runnin like 8-9 lbs max.
Boost is irrelevant mostly to FCO.

It's whatever frequency your AFM is seeing.
 

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Wingless by choice.
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Your may be running to rich like alot of the local cars. runs fine first and then in second it would jump and lerch like a fuel cut, i leaned them out on topend and they are all fast now. What are your AFR's on topend?
 

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i got my prob fixed. I felt stupid cause it wss a line that blew off the VSV under the Intake Mani. the front one that runs to the FPR. All probs fixed now. runs great, just need stickier tires as I found out.
 
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