Welcome to the North American Subaru Impreza Owners Club Saturday September 19, 2020
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo)

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 08-06-2020, 06:12 PM   #1
NicMonte
Scooby Newbie
 
Member#: 479655
Join Date: Dec 2017
Location: Omaha Ne
Vehicle:
2002 Impreza wrx
Black

Default Overboost 02wrx

Iím tuned for 20lbs. I am overboosting to 25lbs for a split second on the logs. Literally just a split second does not hold.

Obviously concerned... what would cause this? And is it of concern if itís just for a split second?

Manifold Absolute pressure:

At 20lbs at 37.319seconds before- 34.19
At 24.73lbs at 37.393seconds later-34.23

Then at 37.415 itís back to 20lbs then tapering etc. Very brief overboost, no check engine lights AFR remains 11.14 throughout boosting.

Thankyou.
* Registered users of the site do not see these ads.

Last edited by NicMonte; 08-06-2020 at 09:11 PM.
NicMonte is online now   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 08-08-2020, 04:07 AM   #2
subaru_gc8
Scooby Specialist
 
Member#: 29292
Join Date: Nov 2002
Chapter/Region: SCIC
Location: Orange County CA
Vehicle:
2004 WRX wagon
silver

Default

what gear? can you do a log?
subaru_gc8 is online now   Reply With Quote
Old 08-08-2020, 02:02 PM   #3
NicMonte
Scooby Newbie
 
Member#: 479655
Join Date: Dec 2017
Location: Omaha Ne
Vehicle:
2002 Impreza wrx
Black

Default


NicMonte is online now   Reply With Quote
Old 08-08-2020, 02:04 PM   #4
NicMonte
Scooby Newbie
 
Member#: 479655
Join Date: Dec 2017
Location: Omaha Ne
Vehicle:
2002 Impreza wrx
Black

Default Overboost 02wrx

Believe this was 3rd or fourth. Iím thinking electrical? MAP sensor is brand new. 3port is brand new.

Itís at 4038 rpm on the second photo.
NicMonte is online now   Reply With Quote
Old 08-08-2020, 02:47 PM   #5
subaru_gc8
Scooby Specialist
 
Member#: 29292
Join Date: Nov 2002
Chapter/Region: SCIC
Location: Orange County CA
Vehicle:
2004 WRX wagon
silver

Default

Quote:
Originally Posted by NicMonte View Post
Believe this was 3rd or fourth. I’m thinking electrical? MAP sensor is brand new. 3port is brand new.

It’s at 4038 rpm on the second photo.
you gotta give us more info, its hard to take a shot in the dark fi you dont let us know mods what trans what gear your pull was in ect. if your not sure, why dont you talke to your tuner about whats going on,
subaru_gc8 is online now   Reply With Quote
Old 08-08-2020, 11:40 PM   #6
NicMonte
Scooby Newbie
 
Member#: 479655
Join Date: Dec 2017
Location: Omaha Ne
Vehicle:
2002 Impreza wrx
Black

Default

Vf48
Pinks
Cobb3port, DP, MAP Sensor
Tgv deletes
Invidia UP
MishimotoTMIC
Walbro255
Jdm205 swapped
Stock5speed(217k miles)Have a 4.44rearLSD waiting to go in.

Tuner has suggested cleaning terminals, and the boost is not real. Logs show as much as i know. stock map was just replaced with the Cobb because of this issue(not the tuners issue, but my own, seeing that boost) He suggested the MAP sensor may be faulty, so I replaced with the Cobb(and obviously tuned for it) and it is still happening.

Reaching out here for some insight and or if anyone has experienced this, as I couldnít find a forum to compare, to what Iím experiencing. Thus my post.
NicMonte is online now   Reply With Quote
Old 08-08-2020, 11:57 PM   #7
subaru_gc8
Scooby Specialist
 
Member#: 29292
Join Date: Nov 2002
Chapter/Region: SCIC
Location: Orange County CA
Vehicle:
2004 WRX wagon
silver

Default

Quote:
Originally Posted by NicMonte View Post
Vf48
Pinks
Cobb3port, DP, MAP Sensor
Tgv deletes
Invidia UP
MishimotoTMIC
Walbro255
Jdm205 swapped
Stock5speed(217k miles)Have a 4.44rearLSD waiting to go in.

Tuner has suggested cleaning terminals, and the boost is not real. Logs show as much as i know. stock map was just replaced with the Cobb because of this issue(not the tuners issue, but my own, seeing that boost) He suggested the MAP sensor may be faulty, so I replaced with the Cobb(and obviously tuned for it) and it is still happening. your afr are a little rich too

Reaching out here for some insight and or if anyone has experienced this, as I couldn’t find a forum to compare, to what I’m experiencing. Thus my post.
uhh I dont think you can just use a cobb map sensor as they read different if you are tuned on the stock stuff you need to stay with the stock stuff... your tuner saying it could be a gake reading is like taking a shot in the dark do you have a boost gauge? if you do compare the 2 if not.. yeah I guess you can just take what he is saying... but yeah not sure he can say that without any proof. but thats me.

so your car shouldt be overboosting unless he is trying to ramp the boost up really quick, some tuners do this but the problem that comes along with that is the overboosting issue.
subaru_gc8 is online now   Reply With Quote
Old 08-09-2020, 01:20 AM   #8
NicMonte
Scooby Newbie
 
Member#: 479655
Join Date: Dec 2017
Location: Omaha Ne
Vehicle:
2002 Impreza wrx
Black

Default

Cobb map sensor is tuned for. Replaced the Oem one due to the same reasons.
NicMonte is online now   Reply With Quote
Old 08-12-2020, 10:56 PM   #9
serrilion
Scooby Newbie
 
Member#: 348982
Join Date: Mar 2013
Chapter/Region: NESIC
Location: Shoreham, VT
Vehicle:
03 OBS
Black

Default

Stuck waste gate? Also I would agree with the overboosting question? Could also be good fuel but not the same fuel the car was tuned with? just some ideas

As for the map sensor could check the voltage readings see if they are in Manufactures specs another idea
serrilion is offline   Reply With Quote
Old 08-13-2020, 09:40 PM   #10
NicMonte
Scooby Newbie
 
Member#: 479655
Join Date: Dec 2017
Location: Omaha Ne
Vehicle:
2002 Impreza wrx
Black

Default

This has occurred on the Stock map sensor W/ td04.
And now occurring on the vf48 w/ Cobb map sensor.

I want to say electrical, but obviously could be dead wrong. When this occurs, nothing happens, itís just a blimp on the accessport.

I might change the alternator, and see if that fixes the issue. I have a theory that there is an electrical boost, and it so happens to be popping up on the Map sensor.

This is a jdm motor, and I kept the alternator on the jdm motor that came with it, and used that. So Ill swap over my old one and see if that fixes the issue.

But I might be dead wrong.

I trust the tuner Iím working with, and he recommended replacing the old map sensor. I bought the Cobb one, because, why not?

This weekend Iíll swap the alternator, and do a pull and take a log. Fingers crossed.
NicMonte is online now   Reply With Quote
Old 08-15-2020, 08:17 PM   #11
FujiSwede
Scooby Newbie
 
Member#: 509169
Join Date: Dec 2019
Default

Double check your vacuum line routing on your 3 port.
FujiSwede is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -4. The time now is 01:53 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2020 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.