Not my car bit helping a friend troubleshoot an issue with his legacy B4, and having a great time learning about sequential turbo setup thay subaru has designed
In a nutshell, symptoms are the code 66 (which now only shows up intermittently after cleaning out the solenoid box, he says it flashes on when he gives it the beans but then it goes away after.) but secondary turbo doesn't seem to be making boost till between 5 and 6k rpm. Hits about 7 psi for normal pull then... nothing till much later on in the rpm range. My initial thought was the air intake control valve wasn't opening until the turbo was forcing it open at a much later rpm. Now I'm thinking the exhaust control valve may be stuck open. Anyone have any similar experience on this type of issue?
One thing I did notice was the line #1 to the air intake control valve actuator seemed to have excess pressure in it when I removed it from the solenoid box with the car off. Is this normal? Isn't the valve actuator controlled by negative pressure?
Any bit of help/knowledge appreciated, cheers.