My gli boost spikes to 12 pounds and if you hold it the car bogs down and the turbo studders. Does anyone know what this could be? Or how it could be fixed.
Similar thing happened to me, this is what was wrong. Im never was able to pinpoint it, but it is almost back to normal now. Just waiting for my coilpack spacers for my TSI coils.
Vacuum line going from boost guage splice to fuel rail was split
Coilpacks/plugs were bad
Upper Y pcv hose was cracked and leaking badly (causing most of the loss in boost)