Boost loss after 1st start?

I have had a reoccurring issue with my vehicle listed above quattro, where when I start it in the morning it runs fine at a good 10lbs of boost past roughly 3,000 RPMs. Usually on the way to work I have to stop at a light, stop sign, ext. After doing so for some reason the turbo only produces 2lbs of boost. (Same issue accurse when I shut off the car then start it). The only way to restore the turbo to 10lbs of boost I have found is to wait roughly 3-4 hours without the vehicle running. It was running lean due to a bad PCV valve which has since been replaced but the issue still occurs.