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Discussion Starter · #1 ·
I believe I have a boost leak from somewhere..... I only boost 13 PSI which seems low but I've noticed in first gear a WOT I overboost to 38 and sometimes I vacuum -38. Also when I'm going into the highway going into work I notice my car start to shake when I get to 4000 RPM mainly in 3rd and 4th gear. Getting a knock of 5.6 rarely but mostly 1.4-2.8. And suggestions on what might be happening and should I be worried? Clutch is worn and does slip but I don't think a slipping clutch would cause the car to shake and cause knock.
 

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Discussion Starter · #2 ·
Just want to make sure I'm not hurting my pistons, AFR seems normal at 14.7 while cruising. I don't drive this car hard unless I'm getting on the highway.
 

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You normally wanna do WOT in 3rd gear from 2k-4500 rpms.

If you think you have a leak. Don't hit boost. Check your lines or do a boost leak test and fix it.

One common area is the IC to TB hose. If you still have the gaskets I'd recommend taking them off and tightening the hose without them
 

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I would do a boost leak test, fix the leak if there is one, and replace the clutch since you already know it's bad.
 

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I'd replace the clutch first, because I've discovered lots of stuff happens doing that, and I'd not want to be troubleshooting a leak or something disconnected twice -- best to just do that after the car has a good clutch in it already.
 

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Discussion Starter · #6 ·
Thanks for all the quick replies. I'll replace the clutch first (getting replaced June 5th) then if it still does it I'll check for a leak. I stay around 4-5 PSI when I'm just normally driving and I don't really drive this car hard unless I see a damn evo trying to act bad hahaha
 

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Discussion Starter · #8 ·
*Update* Clutch is fixed and the shaking at high RPM is gone so I must have had some major slippage. Boost leak was a loose intercooler coupler that damn thing. Still getting some knock but DAM stays at 1 and I'm not getting any knock learn
 

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I was having a problem with not boosting and it was a vac hose that slipped off. It's really common so I hope your fix was as simple as mine.
 
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