Faulty Dump valve?
 

Our 2002 Bugeye WRX feels like its not pulling hard enough. I have cleaned out all the pipes from the boost solenoid and Intercooler. While doing this I check ed the dump valve (Standard one fitted) When I push the piston up and block the small hole at the top the piston returns back to the closed position.

Is this knackered? I thought that with the small hole blocked off the piston should stay up and not drop back down.

What problems would I typically feel with a faulty dump valve.

Thanks

i would of thought it would need some form of suction on the hole to prevent the piston from closing . maybe just covering the hole is not enough...

It's possible the diaphragm inside has seen better days..................

http://www.scoobymods.com/high-milea...th-t12353.html

http://www.scoobymods.com/attachment...7&d=1269197746

But surely if the piston was pushed to the top and the top hole then blocked off creating an enclosed pocket of air inside this would hold the piston in that position? If the piston seal is no good then air would creep out here and the piston return to the bottom.

The "bit" you are pushing up is only the valve plug and not a piston in the OEM valve.

The OEM valve has a rubber diaphragm as per my post above. If you can't see the pictures from Scoobymods let me know.