wastegate extra boost pressure - Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community

bryan.catano93 · 06-23-2018, 12:23 PM

does the wastegate holds in the extra boost pressure after the flap. opens? im running some tests with an air compressor and after the flap opens, it just keeps holding pressure until the hose eventually pops off. it just started doing that now, yesterday i felt the extra air being released somehow.

Sent from my VTR-L09 using Tapatalk

Ultramaroon · 06-23-2018, 02:52 PM

The part to which you are applying pressure is not an open system. It's a diaphragm.

If you felt extra air doing the same thing yesterday, you had a leak. Probably the reason for your overboost. I suggest updating that thread so others can learn from your experience.

Hags86 · 06-23-2018, 05:35 PM

Ultramaroon is correct. The wastegate doesn't (or at least shouldn't) bleed air. When the pressure on it exceeds the spring pressure it pushes open a valve that allows the compresed air to be diverted away from the engine intake.

If you are finding a leak then it's possible that air is leaking, not building enough pressure to open the bupass valve and therefore having manifold pressure higher than the spring pressure.

06-23-2018, 12:23 PM	#1
bryan.catano93 Member Join Date: Feb 2018 Drives: 2013 frs Location: CA Posts: 39 Thanks: 0 Thanked 3 Times in 3 Posts Mentioned: 0 Post(s) Tagged: 0 Thread(s)	wastegate extra boost pressure does the wastegate holds in the extra boost pressure after the flap. opens? im running some tests with an air compressor and after the flap opens, it just keeps holding pressure until the hose eventually pops off. it just started doing that now, yesterday i felt the extra air being released somehow. Sent from my VTR-L09 using Tapatalk

06-23-2018, 02:52 PM	#2
Ultramaroon 義理チョコ Join Date: Sep 2014 Drives: a 13 e8h frs Location: vantucky, wa Posts: 31,868 Thanks: 52,132 Thanked 36,519 Times in 18,920 Posts Mentioned: 1106 Post(s) Tagged: 9 Thread(s)	The part to which you are applying pressure is not an open system. It's a diaphragm. If you felt extra air doing the same thing yesterday, you had a leak. Probably the reason for your overboost. I suggest updating that thread so others can learn from your experience. __________________ service manuals

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
VIDEO GUIDE - Installing Boost/Vaccuum/Oil Pressure/AFR Gauges	The Sentinel	DIY (Do-It-Yourself) Guides	3	04-25-2016 04:43 PM
Boost pressure for built engine	ChrisD	Forced Induction	75	01-06-2016 01:24 PM
Boost Pressure Leak Tester	whitefrs	Forced Induction	32	02-18-2014 02:51 PM

06-23-2018, 05:35 PM	#3
Hags86 Senior Member Join Date: Mar 2013 Drives: Toyota GTS 86 Location: Melbourne Australia Posts: 243 Thanks: 21 Thanked 118 Times in 65 Posts Mentioned: 1 Post(s) Tagged: 0 Thread(s)	Ultramaroon is correct. The wastegate doesn't (or at least shouldn't) bleed air. When the pressure on it exceeds the spring pressure it pushes open a valve that allows the compresed air to be diverted away from the engine intake. If you are finding a leak then it's possible that air is leaking, not building enough pressure to open the bupass valve and therefore having manifold pressure higher than the spring pressure.

User Name		Remember Me?
Password