Hey,
I have a 1991 Celica GT-Four RC and have this issue with the turbo. I don’t know a lot about cars but I will try explain this the best I can.
I’ll be driving along and the turbo will start to spool up and deliver boost at low RPM, up to about 6PSI, then as I accelerate further it will suddenly die off and the engine revs and no power is delivered from the turbo. I don’t see any blue or white smoke and the car drives normal without use of the turbo.
Any ideas as to what the issue might be?
Cheers,