I have a subaru impreza WRX 1996.
On Sunday it just died. The car runs but has severe lack of power. No turbo boost. Top speed is 90 mph. At 5000 rpm a really weired and noisy whoosing noise is heard.
My diagnosis:
1. The turbo spins freely(can be seen by removing air inlet pipe)
2. The vacuum signal (20" Hg) to the dump v/v keeps it open at all times. I have frigged the d.v shut but fault still the same
3. The waste gate actuator is not extended but will start to extend freely to its end limit for a pressure range of 8.0 to 14.4 psi.
If anybody has any ideas / thoughts please let me know as i live in the middle of nowwhere and have no access to a subaru specialist.
Does the car have a limp home mode - could it somehow of reverted to this mode.

 

Limp home mode does kick at 4.5k, so could be. Try a ECU reset first - it might just get rid of it. If not, or if it returns, then perform a fault code check - you may get some pointers as to what to look for...

 

boost cut or limp mode disconnect battery for 1 hour then try the car again and it should boost ok , but it will defo go back into limp mode if something is wrong check fault codes via check engine light on dash and connect the 2 black connectors together under the dash / steering wheel area