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Old 05-09-2022, 03:29 PM   #1
Duffboy253
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Member#: 529239
Join Date: Mar 2022
Default Losing my mind, 07 WRX OVERBOOST :(

Ive been battling this for weeks now, Every time I figure it out, it starts up again.

2007 WRX Wagon, STOCK EVERYTHING, except CAT BACK china exhaust.
160k Miles

Got this to fix up, ended up needing EVERYTHING.

I started with Secondary Air Pump Deleted, Block off kit, Took to tuner to disable codes.

As I was leaving tuner I over boosted in 2nd as I was leaving and entering traffic.

This started everything. Now I started replacing parts, replaced the wastegate soleniod, I never heard my turbo prior to this, so I dont think I was ever getting boost. All this did was cause me to OVERBOOST in EVERY gear now, which made more problems.

First turbo car owner, didnt realize I wasnt getting boost until now.

This lead me on a path to decide the Map Sensor was bad. Key on reading of 30HG, at idle when warm it reads 10HG. From research - it is Key on reading minus Idle reading to give vacuum pressure of 20hg, which is also indicated by my aftermarket mechanical gauge I installed to troubleshoot. So to me this says no vacuum leaks. I also confirmed by using 4 cans of carb clean while my code reader was watching fuel mixture to see if any was getting in, Never found a spot. Bought a used ebay MAP SENSOR it read 57HG key on, and car wouldnt even run.


WASTE GATE ARM. I looked at a ton of stock turbo pictures, my wastegate arm was turned all the way in, no threads showing. So I assumed at some point someone spun it in to try to get the turbo working again, not realizing it was the solenoid????? Spun it out, MARICLE! IT STOPPED OVER BOOSTING, I could red-line it(just to test) and NO OVER BOOST!!!

Victory test drive a day later.... and it OVERBOOSTED again out of no where, and now with no new adjustments, overboosts by 3200 RPM, and im reading 16 PSI on my mechanical on overboost trip. Some times it randomly spikes to 19/20 PSI.

STOCK MOTOR! Other then exhaust.






Please give me something to look for
I also replaced all waste gate solenoid vacuum line with silicone and put the restrictor pill in, the right way, and right depth.

tested the wastegate action with 10PSI and it fully operates.


EDIT: Can a failing turbo cause overboost?
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Last edited by Duffboy253; 05-09-2022 at 03:47 PM.
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Old 05-09-2022, 03:47 PM   #2
NMsubaru25
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Member#: 311718
Join Date: Feb 2012
Location: Maryland
Vehicle:
2002 WRX
PSM

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Edit - I see you did replace the EBCS (which was my first point to mention). Did you buy a used or new OEM one? If you are going to a tuner, just replace the OEM with GS or other aftermarket and get it tuned. If you by chance have a MBC handy or can buy a cheap one, you could install and see if your boost holds steady or not. I had some issues long ago on over boost in a 02 - stock EBCS was bad and aftermarket had to have a tune before it worked right (this was on my first subaru, now I have lost count of how many I had lol).
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Old 05-09-2022, 03:55 PM   #3
Duffboy253
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Boost solenoid was replaced with a new Doorman. Plug and play, didnt think tuning was needed?
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Old 05-09-2022, 04:26 PM   #4
NMsubaru25
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PSM

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Back when I went through the aforementioned scenario (15 or so years ago), I thought my aftermarket EBCS was plug and play too. Subarus can be a bit picky so food for thought. I would go to the part out section or put a WTB and see if you can get a known working OEM one for a quick check from someone for low cost. Good people on here usually willing to help out. I'll dig around and see if I have an extra one as well.
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Old 05-09-2022, 05:25 PM   #5
Duffboy253
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I think I owe you a BJ. I decided to swap in the stock one. While still bad, it didnt over boost!

So I think its been that ****ty doorman all along.

Theres a really good parts place in OREGON, ordered a used OEM one to swap in.

Thanks!!! I think this is the issue.
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Old 05-09-2022, 08:05 PM   #6
K3rm1tth3fr0g
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02' EJ205 20G 6MT wagon

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You also need your restrictor pills in the right spot on a 2 port fyi
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Old 05-09-2022, 09:18 PM   #7
Duffboy253
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Quote:
Originally Posted by K3rm1tth3fr0g View Post
You also need your restrictor pills in the right spot on a 2 port fyi
Yeah, the guys at PIA explained that to me. I got it placed in the exact spot it was, had the hoses side by side.
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Old 05-10-2022, 06:21 PM   #8
NMsubaru25
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Vehicle:
2002 WRX
PSM

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Awesome man, hope it gets resolved with the EBCS!

Saw this today just fyi

https://forums.nasioc.com/forums/showthread.php?t=2936599
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Old 05-10-2022, 11:42 PM   #9
Duffboy253
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Quote:
Originally Posted by NMsubaru25 View Post
Awesome man, hope it gets resolved with the EBCS!

Saw this today just fyi

https://forums.nasioc.com/forums/sho....php?t=2936599
Thanks for the link. I got one from 541 Motorsports(Oregon), REALLY great guys. It was only $30, and they ship fast, so ill get it Thursday to test run.
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Old 05-11-2022, 06:14 AM   #10
Stephafiamson
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Quote:
Originally Posted by Duffboy253 View Post
Ive been battling this for weeks now, Every time I figure it out, it starts up again.

2007 WRX Wagon, STOCK EVERYTHING, except CAT BACK china exhaust.
160k Miles

Got this to fix up, ended up needing EVERYTHING.

I started with Secondary Air Pump Deleted, Block off kit, Took to tuner to disable codes.

As I was leaving tuner I over boosted in 2nd as I was leaving and entering traffic.

This started everything. Now I started replacing parts, replaced the wastegate soleniod, I never heard my turbo prior to this, so I dont think I was ever getting boost. All this did was cause me to OVERBOOST in EVERY gear now, which made more problems.

First turbo car owner, didnt realize I wasnt getting boost until now.

This lead me on a path to decide the Map Sensor was bad. Key on reading of 30HG, at idle when warm it reads 10HG. From research - it is Key on reading minus Idle reading to give vacuum pressure of 20hg, which is also indicated by my aftermarket mechanical gauge I installed to troubleshoot. So to me this says no vacuum leaks. I also confirmed by using 4 cans of carb clean while my code reader was watching fuel mixture to see if any was getting in, Never found a spot. Bought a used ebay MAP SENSOR it read 57HG key on, and car wouldnt even run.


WASTE GATE ARM. I looked at a ton of stock turbo pictures, my wastegate arm was turned all the way in, no threads showing. So I assumed at some point someone spun it in to try to get the turbo working again, not realizing it was the solenoid????? Spun it out, MARICLE! IT STOPPED OVER BOOSTING, I could red-line it(just to test) and NO OVER BOOST!!!

Victory test drive a day later.... and it OVERBOOSTED again out of no where, and now with no new adjustments, overboosts by 3200 RPM, and im reading 16 PSI on my mechanical on overboost trip. Some times it randomly spikes to 19/20 PSI.

STOCK MOTOR! Other then exhaust.






Please give me something to look for
I also replaced all waste gate solenoid vacuum line with silicone and put the restrictor pill in, the right way, and right depth.

tested the wastegate action with 10PSI and it fully operates.


EDIT: Can a failing turbo cause overboost?
You also need your restrictor pills in the right spot on a 2 port fyi
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Old 05-13-2022, 12:01 PM   #11
Duffboy253
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Member#: 529239
Join Date: Mar 2022
Default

UPDATE

Got the new used solenoid in, No overboost, but its only consistently 5 PSI of boost, and when I stomp on it, it surges from 5 PSI to 10 PSI. Its like fluttering

Took it on the freeway, no difference. While coming off the freeway down shifting, when I hit 2nd gear it OVERBOOSTED.

Used OEM Soleniod.

Im really losing my mind now....
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Old 05-16-2022, 06:45 PM   #12
Duffboy253
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No other ideas?



:/
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Old 05-16-2022, 07:07 PM   #13
K3rm1tth3fr0g
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Member#: 508105
Join Date: Nov 2019
Chapter/Region: NWIC
Location: Greater Seattle Area
Vehicle:
Link G4X flex tuned
02' EJ205 20G 6MT wagon

Default

Go to a tuner and stop tearing your hair out
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Old 05-16-2022, 08:09 PM   #14
Duffboy253
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Member#: 529239
Join Date: Mar 2022
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Im going to give them a Call tomorrow.

I dont understand how I am hitting Overboost at 5psi now. and I cant get it to go over 5psi period. I was overboosting at 18+psi before.
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Old 05-16-2022, 10:37 PM   #15
Duffboy253
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Spun the WasteGate arm in 1 full turn, now Im getting proper boost. Ran perfect. then about 2 mins later fluctuating PSI. stopped and Got gas, Now I couldnt make over 5 PSI, then I stopped, engine still running(stop sign), started to go and it ran awesome! and then back to fluctuating PSI.

Got some sort of a ghost, and Im losing it
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