Welcome to the North American Subaru Impreza Owners Club Thursday March 28, 2024
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 04-19-2023, 03:08 AM   #1
Cheesyninja
Scooby Newbie
 
Member#: 533954
Join Date: Apr 2023
Default JDM EJ20Y Help

I have a 2007 JDM Subaru Legacy GT Spec.B 6MT with the twin scroll ej20y, and I have been having an issue with the car bucking/jerking violently under acceleration. It is worse when it is cold, but improves once warm. It occurs under both part and full throttle randomly. Sometimes it happens at 3k, other times at 5k, sometimes not at all. Once it starts bucking, it wont stop until you get off the gas. The car will also start bucking if you shift/start off rough, and wont stop until you get off the gas. The car is also making less boost than normal, capping at 10psi, however I cannot find any boost leaks. I have already replaced the spark plugs, but that did not improve anything. I am at a lost on what to do.
* Registered users of the site do not see these ads.
Cheesyninja is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 04-19-2023, 07:54 AM   #2
Cstricke
Scooby Newbie
 
Member#: 531671
Join Date: Oct 2022
Location: Ontario
Vehicle:
2010 WRX Hatchback
White

Default

When the bucking doesn't happen, are you still making less boost than usual? If so, then my guess would be that there is a boost leak somewhere, or something is wrong with the turbo or some other part of the forced induction system. Having a shop (or yourself) conduct a smoke test is a good way to check for leaks if you haven't done so already.

When you replaced the spark plugs, did you check the coil packs? Apparently they start to separate when they get older, or can sometimes just go bad overtime, both of which can lead to misfires, which could also be what you are experiencing.

Last thing I can think of is to go over your electrical system. Make sure battery cables are securely connected to terminals, that any other wires are still in decent shape and not corroded, and that all grounds in general are good as well.

Mostly just spitballing based on what I've read on here and elsewhere from when I was researching how to deal with a somewhat similar issue with my ej20x (which for the time being has appeared to resolve itself), so hopefully someone else more experienced can chime in. Regardless, hope you're able to get to the bottom of it!
Cstricke is offline   Reply With Quote
Old 04-19-2023, 07:54 AM   #3
Cstricke
Scooby Newbie
 
Member#: 531671
Join Date: Oct 2022
Location: Ontario
Vehicle:
2010 WRX Hatchback
White

Default

When the bucking doesn't happen, are you still making less boost than usual? If so, then my guess would be that there is a boost leak somewhere, or something is wrong with the turbo or some other part of the forced induction system. Having a shop (or yourself) conduct a smoke test is a good way to check for leaks if you haven't done so already.

When you replaced the spark plugs, did you check the coil packs? Apparently they start to separate when they get older, or can sometimes just go bad overtime, both of which can lead to misfires, which could also be what you are experiencing.

Last thing I can think of is to go over your electrical system. Make sure battery cables are securely connected to terminals, that any other wires are still in decent shape and not corroded, and that all grounds in general are good as well.

Mostly just spitballing based on what I've read on here and elsewhere from when I was researching how to deal with a somewhat similar issue with my ej20x (which for the time being has appeared to resolve itself), so hopefully someone else more experienced can chime in. Regardless, hope you're able to get to the bottom of it!
Cstricke 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 05:48 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.