View Full Version : boost problem

03-01-2007, 18:52
Need help i'm new to the site and this is my first subaru,Its a legacy b4 twin turbo
jap import and im having trouble with the turbos when i put my foot down it will only boost when it wants to it usually boost's up to 1.0 or 1.3 bar when its working but when its not working it only boost's to 0.5 bar no matter how hard you floor it and it accelerates like a mondeo.This happens all the time one day it will work fine the all of a sudden it'll stop boosting and it wont start boosting again for a few days.Would be gratefull for any help or suggestions.

B4 Alan
03-01-2007, 19:51
Sounds like a leak somewhere.... is it a standard B4?
AKAIK it should only boost to .7bar as standard :ponder:

When you say it will stop boosting - do you mean not boost at all or just boost at .5bar? Is it a mechanical or electronic boost gauge your using?


03-01-2007, 20:20
its a mechanical guage, it will just boost to .5 bar but when it does this it does'nt feel like there is any boost at all,It's an rsk b4 i'm the first owner in ireland so i dont know the history of the car and i dont know if it has been modified.

B4 Alan
03-01-2007, 21:53
Whereabouts are you based?


03-01-2007, 22:03

04-01-2007, 18:32
Unfortunitly there is several reason's
why she might not be boosting proberly, as Alan
pointed out 1.3bar :shock: :shock: would be very high
from standard .
If she's driving that slow i'd say your cars ECU is in safe mode
more than likley a sensor has gone :ponder: :ponder:

You need to bring her to a garage but your first step might be to get a
main Subaru dealer to do a diagnostic check 50euro. that will tell you if there
is any sensors etc .......gone.


04-01-2007, 19:44
Thanks mate i'll bring it to a main dealer and see what they say.

B4 Alan
05-01-2007, 09:56

Carroll and Roche hooked my B4 up to their diagnostics a few times so it might be worth giving them a shout...