I posted this on NASIOC, as well. http://forums.nasioc.com/forums/showthread.php?t=814767

<sigh> This is the month for Subie problems for me, apparently. A/C compressor clutch froze (replaced compressor). Car started bucking severely - crank position sensor cable was loose (?!?!?), possibly from having Austin Subaru do the fuel rail fix (at least *that* was free). Now, I'm not making more than 7lbs of boost (well, .05 MPa or less). Not to mention that, while looking around under the hood last night, I found a split vaccum hose in the crank ventilation system... grr... I'm beginning to hate this car...

Specs - '02 WRX Wagon, stock (not counting a KartBoy short shifter). Symptoms - doesn't make more than 7lbs of boost, and generally less than that. I'm also noticing what sounds like a new "whine" between 2500 rpm and 3500 - but it may just be turbo spool. Funny that I didn't notice it previously. Recent work - troubleshooting the crank pos sensor issue, including changing plugs, etc.

My understanding is there are several possibilities. The car makes boost - so it's probably not the turbo itself. It could be the wastegate actuator. It could be the boost solenoid. It could be a leak in the air path between the compressor outlet and the intake manifold. Anything else???

Troubleshoot the actuator by putting positive pressure on the running from the "T" to the actuator (and it can't be a bunch of pressure, right, or I can damage the actuator???)??? Also check the actuator manually for appropriate operation?

Troubleshoot the boost solenoid by bypassing and seeing if I can make full boost??? How do I bypass the solenoid?? I see references to doing it, but no "bypassing the boost solenoid for dummies" instructions

Troubleshoot the airpath by taking everything apart and inspecting???

Anything I'm missing?? Can anyone fill in the holes above for me?? Many thanks in advance!!!

 

I'll add some new info. Hoses visually appear to be fine - checked out the air path from the compressor outlet to the throttle body. IC seems to be OK, too.

When detaching the hose from the WG actuator, it fell apart in my hand. The hose is real hard, and just sort of crumbles... There's another part to buy I plugged the other side of the hose. Now boosting to around .06-.07 MPa, instead of .04-.05. My understanding is that, with the actuator disconnected, I should have full boost, period (ie, no boost control?)

Help me, Obi-Wan Kenobi??