Hi! Just picked up a running '97 GF8 (wagon) WRX for dirt cheap - some hail damage, some surface rust, etc. Most prominent issue is with cooling - the car spikes in temperature after a while of driving.

I've drained the coolant and replaced the thermostat and radiator, chased a few leaks down, and replaced all hoses with leaks in them.

The coolant was all gunky. The header tank is all rusted up, so I've given everything as much as a clean as I can.

I've tried to run a coolant flush but nothing is coming out of the turbo coolant return line, despite the turbo coolant feed line (block to turbo) having sprung a leak before (so I know water is getting there).

I tried to reverse the flush (water into the turbo return line, hose out from the header tank to engine block line) but it won't flow. Pressure clearly builds up and the hose pops off. Is my turbo just screwed? What's the problem here? Thanks for taking a look!