The Central Hub for DSM Community and Information

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. This is where the DSM platform history is documented and archived. Log in to help us in our mission, and to remove most ads from the browsing experience.

T25 overboosting ?

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Dsmj89

15+ Year Contributor
3,249
14
Nov 11, 2008
Miami, Florida
For those who know about my project in progress, my new turbo is working fine and dandy. Boosts fine and pulls wonderful, but it is getting a little too happy. Boost keeps rising and rising and i have to let go or ease up on gas. I know this turbo works cause it is the turbo that powered my previous 2g and it worked fine. Seems my actuator arm is stuck closed? What other possibilities could be that i can't think of causing it to overboost ?
As far as i know t25's can't boost creep...
 
Consider yourself lucky as most T25's will drop boost as the RPM's climb and the engine gobbles up airflow.

Perhaps it's a wastegate actuator malfunction, possibly even boost creep depending on the size of your exhaust system and it's restriction....but an overboosting T25 is about as rare as an Albino Sasquatch.
 
Lol @ albino sasquatch, but i agree. My o2 housing and downpipe are stock, after that it is a full 2.5" greddy cat-back exhaust with 2 resonators in place. Also i am running boost off the wastegate. Do you think i should remove the resonators and weld in straight pipes to help with relieving backpressure ?
 
Too little backpressure is what causes boost creep. With your system, boost creep should never be an issue. Removing the resonators will probably do more harm than good at this point.

I would look to a malfunctioning actuator or flapper. Sometimes the sleeve that holds the flapper lever into the turbine housing will walk it's way out a little, causing the flapper to get pinned shut. Check the whole system for free movement and report back.

You can test the actuator for leaks as well as it's movement by supplying it with 20-25psi of air using a blowgun.
 
Thanks jusmx, i will try that out and i'll let you know how it goes.
 
This thread can now be marked as resolved. I changed my wastegate actuator with another one and the problem was solved.
Turbo still pulls and doesn't cry anymore from being overworked.
 
Add Value - Be Respectful - No Trolling - No Misinformation - Participate Often!
Support Vendors who Support the DSM Community

Latest Classifieds

  • For sale 4G63 Frontline Fabrication V2 Billet Valve Cover
    Frontline Fabrication V2 Billet Valve Cover $750 + shipping & paypal fees* swivel AN fittings...
    • jersygsx
    • Updated:
    • Expires
  • For sale 4G63 Race parts.
    It is the time to make room to improve the DSM, getting rid of some extra parts I no longer...
    • GST2012GSX
    • Updated:
    • Expires
  • For sale 1g 1g turbo oil feeds
    1g TD05 oil feeds. Found another box. Have 15 feeds. Have no return lines left. Been running...
    • Galant665
    • Updated:
  • For sale 2g 29 tooth auto speedo
    29 tooth 2g auto speedo. Good condition. Price is shipped. Message 702-741-6987
    • Galant665
    • Updated:
  • For sale 4G63 91 to 96 Auto T Case
    91 to 96 Auto T Case $195 + shipping & paypal feesYou must be registered to see element.You...
    • jersygsx
    • Updated:
    • Expires
Back
Top