Can the fuel tank breather valve system cause boost leaks?

1slowb58 · 08-20-2022, 09:15 AM

I'm trying to track down a massive boost leak on a stage 3 pure 800 340i.

I've gone through the regular suspects already, charge pipe and intake all seem secure. One mechanic used a really cheap boost tap for my meth system on the fuel tank breather line (5). I am going to replace this entire line and the boost tap with a P3 branded one.

Can any of these lines be the cause of the boost leak? I was reading the suction jet line (6) caused boost leaks on the N55 but I'm not sure if this the same situation here.

Any insight appreciated, mods in signature.

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Name: breather.PNG
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B58 · 08-21-2022, 09:32 PM

#5 can because it bolts right on the manifold or throttle body.

Also #6 because it's right on the intake manifold

r510757 · 07-12-2023, 04:22 PM

Did you ever figure out where the boost leak was? I'm facing a similar issue?

08-20-2022, 09:15 AM	#1
1slowb58 Private 40 Rep 99 Posts Drives: 340i xDrive Stage 3 Join Date: May 2021 Location: Toronto iTrader: (0)	Can the fuel tank breather valve system cause boost leaks? I'm trying to track down a massive boost leak on a stage 3 pure 800 340i. I've gone through the regular suspects already, charge pipe and intake all seem secure. One mechanic used a really cheap boost tap for my meth system on the fuel tank breather line (5). I am going to replace this entire line and the boost tap with a P3 branded one. Can any of these lines be the cause of the boost leak? I was reading the suction jet line (6) caused boost leaks on the N55 but I'm not sure if this the same situation here. Any insight appreciated, mods in signature. __________________ 2016 340i xDrive \| Pure 800 \| Dorch S2 \| XHP S3 \| bm3 \| F80 Paul 94 + Meth Custom Tune \| CTS Intake \| VRSF Catless DP \| BMS Elite CP \| Snow Perf VC50 + Dual CM7 CPI \| BC Racing BR Coilovers \| Apec ARC-8 + Hankook Ventus RS4 \| Last edited by 1slowb58; 08-20-2022 at 09:34 AM..
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08-21-2022, 09:32 PM	#2
B58 Major 568 Rep 1,462 Posts Drives: BMW Join Date: May 2018 Location: USA iTrader: (1)	#5 can because it bolts right on the manifold or throttle body. Also #6 because it's right on the intake manifold
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07-12-2023, 04:22 PM	#3
r510757 Registered 0 Rep 1 Posts Drives: Mini F56 Cooper S Join Date: Jul 2023 Location: BC Canada iTrader: (0)	Did you ever figure out where the boost leak was? I'm facing a similar issue?
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